Oklahoma starting quarterback John Mateer, after screenshots of past references to “sports gambling” on his Venmo account surfaced online Monday, denied ever being involved with gambling, saying Tuesday it was instead “inside jokes” with his friends.

School officials became aware of the screenshots late Monday night and are looking into the situation, a source told ESPN’s Pete Thamel.

“The allegations that I once participated in sports gambling are false,” Mateer posted to X on Tuesday. “My previous Venmo descriptions did not accurately portray the transactions in question but were instead inside jokes between me and my friends.

“I have never bet on sports. I understand the seriousness of the matter but recognize that, taken out of context, those Venmo descriptions suggest otherwise. I can assure my teammates, coaches, and officials at the NCAA that I have not engaged in any sports gambling.”

Screenshots posted online Monday night showed Mateer allegedly twice included “sports gambling” in memos for transactions on Nov. 20, 2022, while he was a freshman at Washington State. Both transactions were allegedly made to a Venmo account for Richard Roaten, believed to be a teammate at Washington State at the time.

College athletes are prohibited from betting on any sport offered by the NCAA, with penalties up to loss of eligibility.

OU Athletics issued a statement saying it “takes any allegations of gambling seriously and works closely with the NCAA in any situation of concern.” The school said its “unaware of any NCAA investigation and has no reason to believe there is one pending.”