The college football coaching carousel is one of the more heated aspects of the sport. Either a head coach is leaving a school to accept another job somewhere else, or that coach is getting fired for not doing a good enough job. 

There is not really a good way to leave a school in either circumstance. But for Lincoln Riley, him leaving Oklahoma to take the USC job a few years ago is one of the messiest coach exits in recent memory. 

The Sooners, as well as Riley himself, have drastically different career trajectories since he left Norman, as well. Here's a look back at Riley's exit from OU. 

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When did Lincoln Riley leave Oklahoma?

Riley was named USC's next head coach in late November 2021. He succeeded former longtime Trojans head coach Clay Helton, who was fired in early September that year.

Helton had been USC's head coach from 2015-2021. He was named USC's interim coach after former Trojans head coach Steve Sarkisian took a leave of absence midseason in 2015. He was subsequently fired after reports surfaced that Sarkisian was showing up to practice intoxicated. Helton finished 5-4 as the interim and led the Trojans to 10- and 11-win seasons in 2016 and 2017. But he went 19-14 from 2018-2021 and was fired after USC's 1-1 start in 2021.

Let's just say Sooner fans were not happy when Riley left. 

People are taking this well in Norman. Credit anonymous source via Instagram DMs. pic.twitter.com/Pm2owPPbWU

— Eddie Radosevich (@Eddie_Rado) November 29, 2021

Riley also told the media that his family received death threats amid his departure, although police later said in 2023 that they found no record of his family being threatened.

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Why did Lincoln Riley leave Oklahoma?

Riley had taken over for legendary Sooners coach Bob Stoops after he retired in 2017, previously serving as OU's offensive coordinator from 2015-2016.

He led the Sooners to continued success, including three straight Big 12 titles from 2017-2019 and four straight College Football Playoff berths. He had compiled a 55-10 overall record and had already become the Sooners' fifth-winningest head coach while he was there.

When he was approached about the USC job, Riley felt his success at Oklahoma could translate to Southern Cal.

The Trojans have a storied history, featuring eight Heisman Trophy winners, 11 claimed national titles, and eight perfect undefeated seasons.

"It's such a different opportunity than the one I had at OU," Riley told ESPN's Chris Low in 2022. "And I wouldn't change anything about the one at OU, especially for a first-time head coach. There were some advantages of taking over one like that and some advantages of taking over one like this. But one of my biggest memories when I was younger, junior high and high school when I was already a big college football fan, was watching a game out here on a Saturday night in the Coliseum on a TV screen in Muleshoe, Texas."

Riley had never coached at USC prior to accepting the head coaching job there. He coached at Texas Tech from 2003-2009 and spent four seasons at East Carolina before getting hired by Stoops at Oklahoma. 

"Most of college football fits into small market, average-to-good academics and then your varying degrees of different programs," Riley continued via ESPN. "The combination here of the elite academics and you've got a proven football history -- it's been done here -- and then that big L.A. market, all of that ... I just don't know of anywhere else that has those three."

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Lincoln Riley contract with USC

Lincoln Riley record at USC

Riley is 40-19 across his five seasons at USC. Unlike his time at Oklahoma, he has also failed to win a conference title or make it to the CFP. 

Oklahoma record since Lincoln Riley left

Oklahoma took a similar approach it did in hiring Riley with his replacement, choosing someone with several years of experience. They chose Brent Venables, who had served as OU's defensive coordinator from 1999-2003 before getting elevated to associate head coach/defensive coordinator from 2004-2011. Prior to going back to Oklahoma, he was Dabo Swinney's longtime defensive coordinator and associate head coach from 2012-2021.

Since Riley left Oklahoma, the Sooners have gone 34-22 overall. Oklahoma has had just one CFP berth since then, which came last season and resulted in a home loss to Alabama in the first round. The Sooners are also 0-4 in bowl games since his departure.