49ers bubble players, position competitions to watch on Thursday

The San Francisco 49ers wrap up their preseason schedule on Thursday against the Los Angeles Chargers, and there will be plenty of bubblicious football to enjoy. A sizable chunk of the starters will be sitting out the game, and with double digit roster spots potentially still up for grabs, there is a lot to play for Thursday night.

With that in mind, I thought I would put together a look at some of bubble competitions that will be most worth watching tonight. These are not the only position competitions to watch tonight, but they are the ones that I am particularly intrigued by. What else will you be watching tonight?

Tim Barnes vs. Erik Magnuson vs. Zane Beadles

The trade for Laken Tomlinson opens up a whole mess of questions about the interior line. If Tomlinson gets the starting nod at left guard, Beadles can be depth at all four offensive line positions. If that’s the case, it makes sense to cut Barnes and keep the impressive UDFA Magnuson. Of course, it could depend on what they want to do with their swing tackle role ...

John Theus vs. Garry Gilliam

Gilliam was signed to compete with Trent Brown, but that competition ended not too long after it began. Theus was the tackle who replaced Joe Staley when the latter injured his knee last Sunday. The 49ers likely will sit Trent Brown tonight, so maybe we find out more about how the tackle depth chart actually looks.

Garrett Celek vs. Blake Bell vs. Cole Hikutini

The 49ers traded Vance McDonald, with George Kittle emerging as the primary tight end in the passing game. Logan Paulsen was signed to serve primarily as a blocking tight end. That leaves one maaaaaybe two spots. My guess is the team keeps three tight ends. Kyle Shanahan studied Celek before free agency last year, but never had a chance to sign him following a pre-free agency contract extension.

Quinton Dial vs. Sen’Derrick Marks vs. Chris Jones vs. D.J. Jones

The 49ers interior defensive line is settled in terms of the starting lineup, but the rotation the team expects to use is a big question. D.J. Jones seems the most likely of this group to make the roster, but the big question is what the team plans with Marks. He got a lot of work on Sunday against the Vikings after signing only a few days before. We can expect another big day of snaps tonight against the Chargers.

Tim Hightower vs. Raheem Mostert

I considered Mostert a long-shot heading into camp, and did not think much of him after two weeks, even when he lead the team in rushing in Week 1. But, another big performance, including a huge screen pass for a touchdown in Week 3 has his name buzzing. He’s plenty fast, but I still worry about the Kory Sheets factor with him. On the other hand, Hightower has gotten little playing time. The 49ers know what he can do, but do they go younger as part of their rebuild?

Kendrick Bourne vs. Victor Bolden

The 49ers two UDFA receivers have impressed thus far. Bourne appears to be a receiver worth developing, while Bolden’s speed has impressed on kick returns. If the 49ers think Trent Taylor and/or Jeremy Kerley can be their best return options, it might make more sense to keep Bourne. But if Bolden impresses against the Chargers, he would make this decision significantly harder.