The search is underway in Norman.
The Oklahoma football team took a crushing blow on Sunday after numerous reports that head coach Lincoln Riley accepted an offer to become the new shot caller at USC.
Riley went 55-10 during his five seasons at the helm of the Sooners' program, and he leaves behind what is arguably now the most desirable coaching vacancy in the country.
Here are five candidates for Riley's replacement at OU:
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A return to Norman for Brent Venables would be fitting.
The Clemson defensive coordinator served as a member of OU's staff from 1999-2011. He spent time as a defensive coordinator, linebackers coach and an assistant head coach during his time with the Sooners.
Venables has experienced plenty of success since joining Clemson's staff in 2012. The Tigers have won two national championships, and Venables won the 2016 Broyles Award, which went to the nation's top assistant coach.
Venables' experience with both the program and the College Football Playoff makes him an ideal candidate to lead OU when it makes the move to the SEC no later than in 2025.
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Shane Beamer also has a connection to the Sooners.
The South Carolina head coach served as OU's assistant head coach from 2018-20. He was a part of the staff that coached the Sooners to a nation-leading scoring offense in 2018, averaging 48.4 points per contest.
The Gamecocks improved from 2-8 in 2020 to 6-6 this season under Beamer, and the first-year head coach also showed his skills on the recruiting trail by securing commitments from four four-star recruits.
Beamer signed a five-year deal worth $2.75 million per year with South Carolina on Dec. 15, 2020, but he would be in for a pay raise if OU came calling.
More: Lincoln Riley leaving OU football for Southern Cal after five seasons as head coach
Perhaps no program in the country experienced as big of a comeback as Baylor did this season.
After going 2-7 last season in Dave Aranda's first year as head coach, the Bears finished the 2021 regular season with a 10-2 record and a ticket to the Big 12 Championship Game against Oklahoma State.
Aranda spent four seasons as LSU's defensive coordinator before arriving in Waco, and he was a part of the Tigers' national championship run in 2019.
Aranda has been a popular name in the coaching carousel lately. He was connected to the Florida and USC openings, which are now both filled, and he remains an obvious candidate for LSU's vacancy.
Dennis Dodd of CBS Sports reported on Friday that Aranda is expected to sign an extension with Baylor sometime over the next two weeks, but that could change now that OU is searching for a new head coach.
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Iowa State took a massive leap last season thanks to Campbell.
After leading the Cyclones to a 2-7 record during his first season as the head coach in 2016, Campbell coached the program to a 9-3 record in 2020.
Iowa State entered the 2021 campaign as OU's biggest threat to the conference crown, but it finished the regular season with a disappointing record of 7-5. Despite this, Campbell is still a two-time Big 12 Coach of the Year and one of the most desirable candidates in the country.
USC also expressed interest in Campbell before ultimately going with Riley, but the six-year Iowa State head coach should get some consideration in Norman.
Campbell's contract buyout is a whopping $28.3 million, though, which makes his departure from Iowa State unlikely.
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OU has a good track record of hiring from within.
The decision to hire Riley as its head coach following the retirement of Bob Stoops worked out well, and Alex Grinch could be another example.
The OU defensive coordinator turned a group that ranked 101st in total defense in 2018 to 28th in 2020. Grinch's stock fluctuated this season as the Sooners' defense experienced ups and downs, but there's no denying his impact on the program since joining the staff three seasons ago.
Grinch interviewed for the head coaching position at Texas Tech earlier this month, according to many reports, but that spot has since been filled by Baylor assistant Joey McGuire.
When asked about his interest in eventually becoming a head coach on Nov. 9, Grinch made his aspirations clear.
"It's there," Grinch said. "It absolutely is, and that's something for the offseason."
Justin Martinez can be reached at email@example.com or @JTheSportsDude on Twitter. Make sure to subscribe to The Oklahoman to stay up to date with all local sports.
This article originally appeared on Oklahoman: OU football coaching candidates to replace Lincoln Riley