What to watch for: 49ers-Chiefs

Here are five positions fans should keep an eye on during tonight’s preseason game between the San Francisco 49ers and Kansas City Chiefs at Arrowhead Stadium at 5 p.m. PT on KPIX 5 and CW Bay Area.

Quarterback

Under head coach Jim Harbaugh, Colin Kaepernick and Alex Smith both led Greg Roman’s empire to success. But tonight, the former teammates duel for the first time, however brief it might be.

Both will show off the Chris Ault pistol, as the ex-Nevada head coach is now consultant to Chiefs head coach Andy Reid. More importantly for the 49ers, though, is establishing depth at the backup job among Scott Tolzien, Colt McCoy, and B.J. Daniels, who gets his first chance at quarterback tonight.

Wide Receiver

The 49ers need someone to step up and take the No. 2 spot opposite Anquan Boldin. They prefer it be the speedy A.J. Jenkins, but after watching practice this week it’s clear that Austin Collie or Kyle Williams would better serve Kaepernick as a target there.

Collie had eight catches including two red zone TD’s at Wednesday’s practice where Williams also made a highlight grab on a sideline fade route from Kaepernick.

Tight End

Undrafted dread-locked quarterback turned tight end MarQueis Gray was solid all week with second-rounder Vance McDonald not practicing.

Gray should get a number of opportunities this evening and is a serious contender to make the 53-man roster.

Cornerback

In the wake of Chris Culliver’s season-ending ACL tear, Tramaine Brock has reclaimed his 2011 job as the No. 3 corner for the time being, but the versatile Perrish Cox was outstanding against the Broncos last week, and Nnamdi Asomugha is fighting for a job as well.

It’s feasible to see all three on the 53-man roster, but in what rotation is unclear. Expect very hard play from all three tonight.

Punter/Kicker

Former UC Davis punter Colton Schmidt drew praise from Harbaugh at Wednesday’s press conference and later drilled a pair of 40-yard field goals in practice.

With the ability to put the ball in the endzone on every kickoff, blast hanging punts, tackle, and possibly hit field long-range field goals, the undrafted rookie is fast becoming a weapon worth keeping in the arsenal.

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