Oklahoma coach Lincoln Riley has a quarterback quandary on his hands. Or does he?

Caleb Williams was supposed to do for Oklahoma in 2021 what Bryce Young did for Alabama in 2020: hold a clipboard, take garbage-time snaps, impress coaches and teammates on the scout team and bide his time until the moment inevitably came when he'd take control of the offense.

In the latest twist in an unpredictable rivalry, the Sooners' 55-48 win against Texas in the Red River Showdown was keyed by the true freshman, who threw for 212 yards and ran for another 88 with three touchdowns after replacing an ineffective Spencer Rattler.

The play of these two passers — with Williams on the rise and Rattler cratering under huge expectations — will leave coach Lincoln Riley facing the first true quarterback dilemma of a tenure defined by his ability to turn any option at his disposal into a Heisman Trophy contender.

Will it be Williams, who has done nothing but impress since arriving on campus earlier this year? Or will it be Rattler, who was pegged as the nation's best quarterback in August but hasn't come close to meeting the hype?

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Behind an improved defense and a manageable regular-season schedule, it's this question that will determine whether Oklahoma can return to the College Football Playoff and then advance against one of the top teams from the SEC.

In part, Rattler's reputation was built on the idea that every OU quarterback who came under Riley's direction had either won the Heisman, like Baker Mayfield and Kyler Murray, or come close, like Jalen Hurts.

Oklahoma's Caleb Williams celebrates after defeating Texas in the Red River Showdown.
Oklahoma's Caleb Williams celebrates after defeating Texas in the Red River Showdown.

But the performance hasn't been there in his second year as the starter, making Rattler the face of the Sooners' first half of the regular season: good, even better than most, but not good enough.

Fresh off the spark he provided Saturday, there may be no better time for Riley to turn the offense over to the true freshman. OU is about to enter the soft middle of its schedule: next comes TCU, Kansas, Texas Tech and Baylor before ending the regular season against Iowa State, Oklahoma State and, presumably, in the Big 12 championship.

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The question is which quarterback gives OU the best chance at completing a perfect season, especially given the largely solid play of a defense that was burned early by Texas but held the Longhorns out of the end zone from the midpoint of the second quarter until one minute left in the fourth.

The argument for Rattler is his relative experience and the idea that the same quarterback once picked as a top Heisman contender can rediscover his form. For Williams, it's about the promise and potential he brings to an underachieving offense.

For the first time in a largely spotless tenure, Riley will have to make a decision that will ripple through the Football Bowl Subdivision. The right choice could lock the Sooners into the playoff, with the potential for more.

Follow colleges reporter Paul Myerberg on Twitter @PaulMyerberg

This article originally appeared on USA TODAY: Spencer Rattler or Caleb Williams? Oklahoma coach must choose QB