Nelson, out of Los Alamitos High School in California, committed to Oklahoma in July but wrote on Twitter that he was decommitting "in light of the recent events and changes."
Riley had been instrumental in Nelson's recruitment and a big part of why he chose the Sooners in the first place.
"One of the things that attracted me most to OU, other than the rich history and amazing fans, was the stability in the coaching staff and their ability to develop the QB position," Nelson wrote.
Also decommitting on Sunday were class of 2022 linebackerKobie McKinzie, and ESPN Jr. 300 receiverBrandon Innissand running back Treyaun Webb, both of the 2023 class.
McKinzie is the 95th-ranked recruit for '22, according to ESPN, and had been committed to the Sooners since January 2020.
Inniss, a 6-foot, 190-pound recruit out of American Heritage High School, is the No. 6 prospect in Florida and No. 29 overall, per ESPN's rankings.He had been committed to Oklahoma since Aug. 23.
Webb, from Jacksonville, Florida, and ranked No. 152 in the ESPN Jr. 300, had originally committed to Oklahoma over Georgiaand Ohio Statein July.
"First off, I would like to thank the University of Oklahoma and the coaching staff for believing in me and welcoming me with open arms," Webb wrote in a tweetSunday evening. "It has been a wild recruiting process for me to say the least, but at the end of the day, I have to do what's best for me. With that being said, due to the recent changes, my family and I have decided it is in my best interest to decommit from the University of Oklahoma."
Nelson,McKinzie, Inniss and Webb were not the only recruits to react to Riley's departure. ESPN 300 running back and Oklahoma commit Raleek Brown told ESPN on Sunday, before the Trojans announced the hire, that Riley's move will affect his recruitment.
"That changes everything," Brown said after ESPN and other outlets reported earlier Sunday that Riley would replace Clay Helton atUSCafter five seasons with Oklahoma. "I had a good relationship with all [the Oklahoma coaches], so that will really change everything."
Brown is the No. 60-ranked prospect overall and the No. 2 recruit in California, according to ESPN. He's a 5-7, 170-pound back from Mater Dei High School in Santa Ana, and has been committed to Oklahoma since February.
USC had been a school of interest for Brown before he chose Oklahoma, but similar to other recent California recruits, he chose to go out of state.
USC has signed only 30 of the 143 ESPN 300 recruits from California over the past five recruiting cycles, but Brown believes Riley coming to the school could stop that trend.
"It's exciting news for everybody," Brown told ESPN. "He's a great head coach, you could just tell what he was doing at Oklahoma. So, this is a big step for USC, and I think he's going to bring it back to what it was -- packed stadiums and all that."
Brown is one of three class of 2022 and '23 recruits from California who is committed to Oklahoma. He's joined by DeAndre Moore Jr.and Makai Lemon, both ESPN Jr. 300 receivers and teammates of Nelson.
Lemon posted an ambiguous tweet after the Riley news surfaced, writing, "hmmm," but has not commented on his commitment status.
Moore has also not commented on the hire or whether it impacts his recruitment.
Oklahoma currently has 10 ESPN 300 commitments in the 2022 class with a little over two weeks remaining until the early signing period. With Nelson, Inniss and Webb no longer a part of their 2023 class, the Sooners now have three ESPN Jr. 300 commitments.
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