Statistical Preview of 2009 Free Agency: II. Right Tackles

On Tuesday, I previewed free agents at the QB position. I found that recent NFL playoff teams have either drafted their QB in the 1^st round (if they were several players away from contention), or signed an old, established QB (if they were 1 or 2 players away from contention). Based on the poll results, most of you thought the Niners would be better off by going the later-round QB route. Of those who voted for the free agent route, most thought Jeff Garcia is the best option. Based on your votes, then, it seems like you think the Niners are on the brink of playoff contention. I tend to agree.

Today in Part 2 of my free agency preview, I'll break down the likeliest free agent possibilities at RT (Note: I don't want to short-shrift the FBs, so I'm doing a separate post for them on Saturday). As in Part 1, I'll begin with an argument for evaluating only a select group of RTs that fit a certain profile. Then, I'll present the available stats, and conclude by ranking the specific free agent RTs who fit the profile.

IDENTIFYING THE TARGET(S)

In 2008, the 49ers' RT position saw more turnover than JT O'Mulligan. Oft-"injured" Jonas Jennings started the first 2 games, and then, well, got "injured." Barry Sims replaced Jennings and started 6 games before hurting his ankle, which forced Adam Snyder to slide over to RT. Snyder started the next 6 games until, you guessed it, he got injured. Snyder's injury allowed Sims to re-enter the starting lineup, which is where he remained for the final 2 games of the season. So in total, Sims started 8 games at RT, Snyder started 6, and Jennings started 2. To put that in perspective, no other team in the NFL had a RT that started fewer than 11 games, and 20 of the 32 teams had their RT start all 16 games. Therefore, having 3 different starting RTs during the season, and having no RT start more than 8 games, makes the 2008 49ers what, in statistics, we'd call an "outlier." More importantly though, when a team prefers running to the right side of the line, as the 49ers do, 3 starters at RT is not a recipe for success.

Based on the above, the Niners need a starting RT...stat (pun intended)! Before evaluating specific free agent RTs, though, we need to answer two questions. First, is a team more likely to make the playoffs if they sign their starting RT in free agency? Second, and perhaps more fundamentally, where do starting RTs come from? Below is a table that will help us answer these questions. It displays various characteristics of "starting" RTs in the NFL circa 2008 (i.e., those with 8 or more starts) :

Player	Team	How Acq	Age Acq	Round	College Pos	NFL Pos
Carey	MIA	Draft	--	1	LG/RT	RT (MIA) --> LT (MIA) --> RT (MIA)
Diem	IND	Draft	--	4	RT	RG (IND) --> RT (IND)
Brown, L.	ARI	Draft	--	1	LT	RT
Otah	CAR	Draft	--	1	LT	RT
Cherilus	DET	Draft	--	1	RT/LT	RT
Barron	STL	Draft	--	1	LT	RT
Cook	MIN	Draft	--	2	C	RT
Stinchcomb	NO	Draft	--	2	RT	RT
Trueblood	TB	Draft	--	2	LT	RT
Jansen	WAS	Draft	--	2	RT	RT
Harris, R.	DEN	Draft	--	3	LT	RT
Winston	HOU	Draft	--	3	LT	RT
Kaczur	NE	Draft	--	3	LT	RT
Locklear	SEA	Draft	--	3	RT/LT/RG	RT
Andrews, Sta.	CIN	Draft	--	4	DNS	RT
Colon	PIT	Draft	--	4	RT	RT
Stewart, D.	TEN	Draft	--	4	RT	RT
Clary	SD	Draft	--	6	RT	RT
Tauscher	GB	Draft	--	7	RT	RT
Clabo	ATL	FA	23	ND	LT/LG	RG (ATL) --> RT (ATL)
Shaffer	CLE	FA	26	7	LT	LT (ATL) --> LT (CLE) --> RT (CLE)
McIntosh	KC	FA	30	3	LT	LT (SD) --> LT (MIA) --> LT (KC) --> RT (KC)
Sims	SF	FA	33	ND	LT	LT (OAK) --> LG (OAK) --> LT (OAK) --> RT (SF)
Colombo	DAL	FA	26	1	LT/RT	LT (CHI) --> RT (CHI) --> RT (DAL)
McKenzie	NYG	FA	26	3	LT	RT (NYJ) --> RT (NYG)
Runyan	PHI	FA	26	4	LT	LT (TEN) --> RT (TEN) --> RT (PHI)
Pashos	JAC	FA	27	5	RT	RT (BAL) --> RT (JAC)
Walker, L.	BUF	FA	28	2	LT	LT (OAK) -->RT (OAK) --> RT (BUF)
Tait	CHI	FA	29	1	LT	LT (KC) --> RT (KC) --> RT (CHI) --> LT (CHI) --> RT (CHI)
Woody	NYJ	FA	30	1	C	C (NE) --> LG (NE) --> RG (DET) --> RT (DET) --> RT (NYJ)
Green, C.	OAK	FA	30	ND	LT/RT	RT (DEN) --> LT (TB) --> RT (OAK)
Anderson, W.	BAL	FA	33	1	LT	LT (CIN) --> RT (CIN) --> RT (BAL)

After the jump, I'll discuss the table, identify 4 free agent RT targets, and pick the one whose stats best fit what the Niners are looking for (aka a run-blocking RT)...

As I'm apt to do, first let me take care of some housekeeping. In the "How Acquired" column, FA means free agency. In the draft round column, ND means the RT was not drafted by any team. In the college position column, I've listed the RT's primary college position first, and Stacy Andrews' DNS means he wasn't a regular starter in college (DNS = did not start). In the NFL position column, I've tracked the OL position at which each player has been the "starter" during his career (i.e., I don't include short position changes as an injury replacement); with the team for which he played the position indicated in parentheses. Finally, the reasons for bold italics in the team and NFL position columns will become clear very shortly. Alright, back to the show...

To answer our first question, take a look at the teams in bold italics. Those are the 2008 playoff teams. As you can see, 8 of the 12 drafted their starting RT. Of course, this is only 1 season, but the trend holds when you look at previous seasons (e.g., 9 of 12 playoff teams in 2007 drafted their RT). Therefore, the evidence suggests that the 49ers should actually draft their starting RT. Although this isn't the focus of my article, the table also seems to suggest that, when drafting a starting RT, it doesn't really matter which tackle position the RT played in college. As you can see from the last 2 columns, it appears that NFL teams draft a player with the intent of making him their starting RT regardless of what tackle position he played in college. Furthermore, once such a player gets drafted, he's inserted at RT and almost invariably stays there for the length of his tenure with the team (17 of 19; See bold italics associated with draftees).

In the NFL, there's an adage that says a team's RT is usually a player they've converted from LT. As I just showed you, this is definitely not true with respect to starting RTs acquired in the draft. But how about starting RTs acquired via free agency? This time, look at the last column. As they relate to free agency, the bold italics in this column indicate that the player had started at RT before signing with his current team. Therefore, as the last column shows, 9 of the 13 starting RTs who were acquired via free agency had been a starting RT in the NFL prior to being signed. Of the 4 who weren't (Clabo, Shaffer, McIntosh, and Sims), Clabo started out at RG and Sims wasn't signed to be a starter on the OL. Therefore, going back to the NFL adage, it turns out that only 2 of the 32 starting RTs in the NFL (Shaffer and McIntosh) were acquired to start at LT with their current team, only to move to RT later.

One other point I'll make about the table is this: In contrast to my QB breakdown in Part 1, nearly all of the starting RTs who were acquired as free agents were signed before they were 31 years old; 11 of 13 to be exact.

In summary, then, looking at the characteristics of starting RTs suggests three things related to free agency. First, playoff teams are more likely to have drafted their RT than acquired him via free agency. Second, starting RTs who were acquired via free agency are likely to have started at RT with a previous NFL team. Finally, starting RTs who were acquired via free agency were likely to have been signed before the age of 31.

THE LITTER

Here's how I would apply the above analysis to the 49ers' current situation:

• They should probably draft their starting RT rather than sign him as a free agent.

• If they choose to sign a free agent to be their starting RT, that free agent should already be a starting-caliber RT in the NFL. Also, he should preferably be younger than 31.

Here are the only 3 free agent tackles who meet the previous-RT-starter and under-31 criteria, plus 1 other free agent who's close on age but meets the experience criterion:

Vernon Carey, age 28

Mark Tauscher, age 32

Jon Stinchcomb, age 29

Stacy Andrews, age 28

As I alluded to earlier, the 49ers' run tendencies (~25% runs to the right, ~20% runs to the left) dictate that its starting RT is supposed to be its best run-blocker on the OL. In the seasons preceding 2008, this was generally the case on the right side of the Niners' OL: Kwame Harris's run-blocking was his only marketable skill - unless holdng, false starting, and whiffing on pass blocks are marketable - and Vernon Davis's run-blocking has been turning into his only marketable skill. Therefore, to evaluate the 4 free agent RTs I've identified as targets, I'm going to use 1 indicator of run-blocking ability (directional ALY), 1 indicator of how much the free agent's previous team ran his way (i.e., to the right; % of directional carries compared to league average), and 2 indicators of team running performance (team ALY and team rush offense DVOA). For each player, I'm going to present the relevant stats covering their last 3 seasons as a starting RT, along with their 3 year averages.

Here are the relevant stats for Carey, Tauscher, Stinchcomb, and Andrews:

Vernon Carey	28 yo
Year	Team	RT ALY	Rk	Net Team RT Carry %	RE ALY	Rk	Net Team RE Carry %	Team ALY	Rk	Team Rush DVOA	Rk
2005	MIA	4.21	15	1.0%	3.92	17	0.0%	4.33	11	-5.5%	14
2006	MIA	4.76	2	4.0%	4.91	6	2.0%	4.20	20	-12.6%	28
2008	MIA	4.51	9	0.0%	4.93	3	3.0%	4.25	12	4.8%	12
3-yr Avg		4.49	9	1.7%	4.59	9	1.7%	4.26	14	-4.4%	18

Mark Tauscher	32 yo
Year	Team	RT ALY	Rk	Net Team RT Carry %	RE ALY	Rk	Net Team RE Carry %	Team ALY	Rk	Team Rush DVOA	Rk
2006	GB	4.30	11	3.0%	3.43	26	1.0%	4.27	16	-8.1%	23
2007	GB	4.23	17	3.0%	3.45	27	9.0%	3.95	26	3.3%	9
2008	GB	3.73	27	1.0%	3.24	27	9.0%	4.17	18	-0.5%	19
3-yr Avg		4.09	18	2.3%	3.37	27	6.3%	4.13	20	-1.8%	17

Jon Stinchcomb	29 yo
Year	Team	RT ALY	Rk	Net Team RT Carry %	RE ALY	Rk	Net Team RE Carry %	Team ALY	Rk	Team Rush DVOA	Rk
2006	NO	3.91	28	-2.0%	4.42	11	0.0%	4.37	12	2.3%	10
2007	NO	3.98	23	-3.0%	3.77	21	2.0%	4.39	7	-5.9%	18
2008	NO	4.32	13	4.0%	3.24	28	3.0%	4.43	6	6.6%	8
3-yr Avg		4.07	21	-0.3%	3.81	20	1.7%	4.40	8	1.0%	12

Stacy Andrews	28 yo
Year	Team	RT ALY	Rk	Net Team RT Carry %	RE ALY	Rk	Net Team RE Carry %	Team ALY	Rk	Team Rush DVOA	Rk
2006	--	--	--	--	--	--	--	--	--	--	--
2007	CIN	3.29	31	5.0%	3.43	25	0.0%	3.37	32	-15.0%	32
2008	CIN	3.24	31	4.0%	4.82	4	-2.0%	4.25	12	-4.0%	15
3-yr Avg		3.27	31	4.5%	4.13	15	-1.0%	3.81	22	-9.5%	24

Just so you know, the numbers in the "Net Team Carry %" columns tell you the frequency that the player's team ran in that direction compared to the league average frequency. In these columns, positive values mean that the team ran more often than league-average in that direction, whereas negative values mean the team ran less often than league-average in that direction. OK, onward ho...

As you can surmise from the tables, each free agent RT has his statistical strengths and weaknesses. In terms of strengths, Carey has the best RT and RE ALY averages, Stinchcomb has the best team ALY and rush DVOA averages, Andrews' team has the highest net % of runs behind RT, and Tauscher's team has the highest net % of runs toward RE. In terms of weaknesses, Andrews is worst in 4 of the 6 stats, Stinchcomb's team has the lowest net % of runs toward RE, and Tauscher has the worst RE ALY.

Due to such a high amount of ranking variability between stats, it's useful to make a judgment about how relevant each stat is as a measure of RT performance. Obviously, the most important stat is RT ALY because it's most specific to the player in question. Analogously, team rush DVOA is probably the least important stat because it's least specific to the player in question. Going from most to least player-specific among the other 4 stats, I'd rank them as follows: (1) average net % of team runs behind RT, (2) RE ALY, (3) average net % of team runs toward RE, and (4) team ALY. Having done this little exercise, we can now use this stat-specificity rubric to weight each free agent's stat rankings*, and thereby determine how each free agent RT ranks overall among the 4.

PICK OF THE LITTER

Here's how the 4 free agents rank statistically after weighting their individual rankings according to how specific each stat is to the RT position:

1. Vernon Carey
2. Mark Tauscher
3. Stacy Andrews
4. Jon Stinchcomb

It turns out that the rankings are basically the same as if I would have ranked them according to RT ALY. The only difference is that Andrews leapfrogs Stinchcomb after applying the weights. This occurred because, although NO has been a better running team than CIN, NO has run much less frequently behind Stinchcomb than has CIN behind Andrews. In the end though, their weighted rankings are nearly identical (only a 1 point difference), so it's certainly within reason to say that the two have been equals when it comes to performance.

What's reasonably clear, however, is that Carey and Tauscher have been considerably better than Andrews and Stinchcomb in their previous 3 seasons as starting RTs. In terms of a comparison between Carey and Tauscher, their difference emerges mainly from Carey's superior RT and RE ALYs. The fact of the matter is that, although GB has run behind Taushcher more than MIA has behind Carey, the difference in RT run frequency is actually quite small. Furthermore, despite GB's decided preference for RE runs, MIA has actually been head-and-shoulders better than GB at blocking on runs toward RE. The amount of credit given to Carey for MIA's RE ALY, or blame given to Tauscher for GB's RE ALY, is certainly debatable. Nevertheless, what's not debatable is that MIA has been better than GB at blocking runs behind RT. Carey has been MIA's starting RT during that time, so he wins out.

On Saturday, I'll be previewing the FBs. TO BE CONTINUED...

*I used the stat-specificity weights like this. There were 6 stats, so the most specific stat got a weight of 6, the next-most specific stat got a weight of 5, and so on. I multiplied these weights times the reverse of each player's ranking among the 4. For example, Carey was #1 on RT ALY, so he got a score of 4 for this stat. RT ALY had a weight of 6, so I multiplied 6 times 4 to get a ranking score of 24 for Carey in RT ALY. After doing this for all 4 players' rankings on all 6 stats, I added the ranking scores for each player. The end result was Carey 67, Tauscher 56, Andrews 44, and Stinchcomb 43; hence, my pecking order.

**DVOA and ALY statistics used to produce this article were obtained from Football Outsiders.