49ers vs. Chiefs: 5 must-watch players in 2021 preseason opener

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Ambry Thomas #20 of the San Francisco 49ers (Photo by Thearon W. Henderson/Getty Images) /

49ers Player to Watch No. 1: Cornerback Ambry Thomas

If there’s one position considered a glaring weakness for San Francisco in 2021, it has to be cornerback.

Especially the depth.

The starting duo of Jason Verrett and K’Waun Williams must stay healthy, while No. 2 boundary cornerback Emmanuel Moseley has to continue his solid training camp play into the regular season and retain those starting duties.

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Until the 49ers’ third-round draft pick, Ambry Thomas, comes around.

Thomas has had his up-and-down moments in camp thus far. The former Michigan cornerback who opted out of his 2020 campaign in light of the pandemic has looked like a rookie a lot during training camp, and it’s common for young defensive backs to struggle anyway early on in their pro careers.

Considering the Niners don’t have a lot of proven depth at the position, leaving few other options to guard against injury, Thomas’ development is going to be vital to help reinforce that depth behind Verrett, Moseley and Williams.

Saturday’s bout against the Chiefs might give a pretty good indication of whether Thomas is well on his way to a prominent role or if he remains a work in progress.

Next. 4 reasons why 49ers are Super Bowl contenders in 2021. dark

San Francisco and Kansas City kick off on Saturday, Aug. 14 at 8:30 p.m. ET from Levi’s Stadium.