A look at D.J. Reed’s free safety work in place of Adrian Colbert in Week 4

As I mentioned earlier, one of the biggest surprises four weeks into the season is that the 49ers are having issues in their secondary. At the tail end of last year, it seemed like two rookies had locked up starting jobs for 2018 — CB Ahkello Witherspoon and FS Adrian Colbert.

Colbert, a seventh-round pick in 2017, flashed in the last few games last year and suddenly became a fan favorite. The 6-foot-2 safety finished the season with 37 tackles, a couple of forced fumbles and five passes defensed in 14 appearances. Heading into training camp, it seemed like the position was Colbert’s for the foreseeable future.

Yet, in the 2018 NFL Draft, the 49ers’ brain trust chose to use a 5th-round pick on an electric defensive back, D.J. Reed, out of Kansas State. After immediately earning the nod as a kick returner due to his blistering straight-line speed, Reed also has his eyes set on the free safety job.

Colbert left with a hip injury in Week 3 against the Chiefs, allowing Reed to step in and impress the defensive coaching staff. With Colbert sidelined for a majority of the week during Week 4 practices, Reed earned the start this past Sunday at Los Angeles.

“I think I was happy with Reed’s play...I thought Reed did a good job in the game. Improvement from last week before. I think he’ll continue to get better with more reps,” Kyle Shanahan pointed out this week when asked about the rookie’s performance.

When asked about who the starting free safety would be this weekend against the Cardinals, Shanahan added, “I think Colbert will be healthier this week, which will give Colbert a much better chance to get his spot back. We’re one day into this. We’ll see by Wednesday how much better he is. But, I expect Colbert to get out there eventually, but D.J. got his opportunity because of health reasons. Sometimes all a guy needs is an opportunity. We’ll see how this week goes.”

It sure sounds like once Colbert is healthy, he’ll get his starting job back, but how did Reed look on the field Sunday against quarterback Philip Rivers and the Chargers?

While Reed only accounted for two tackles this past Sunday, I think one of the biggest pointers for his success was Rivers’ hesitancy to throw the ball deep. One of the NFL’s gun slingers, Rivers always wants to push the ball down field, yet on Sunday, Rivers seemed hesitant to do so.

On this first play here, Reed is shading over the left side of the field, allowing Chargers’ running back Austin Ekeler to be lined up one-on-one against 49ers’ linebacker Fred Warner. Rivers stares down Ekeler the entire way and finds him open for a touchdown down the right sideline. It seemed like Reed shifted over late and couldn’t get to Ekeler in time.

On this next play, 49ers’ corner Jimmie Ward is lined up against Chargers’ wideout Tyrell Williams, where Williams makes a sensational grab. Once again, Reed is on the opposite side of the field, but is able to race over to tackle Williams immediately after the catch. Reed’s speed is on display here, not allowing any yards after the catch.

The 49ers’ poor tackling this season has been well documented and here’s an example of exactly what they can’t be doing. Reed races over to Chargers’ running back Melvin Gordon and should be able to wrap him up on the sideline and prevent the Chargers’ running back from gaining extra yards.

Instead, Reed puts his head down and tries to blindly hit Gordon, who bounces off and gains a handful of yards after. Reed has to clean up his tackling and can’t afford to miss tackles this poorly, especially if he aims to keep his starting job.

Just as poor of a play the last one was, this next one was the absolute opposite. After Ekeler makes the catch, Reed seems like he’s running at a different speed than everyone else on the field, finishing off the tackle on the Chargers’ running back immediately.

The 49ers have two solid athletes competing to be their starting free safety, but I’d lean on the side of starting Colbert for the time being. Reed’s explosive and his speed in the back would be phenomenal, but I’ll take Colbert’s experience in the short term.