The New York Jets’ wacky quarterback situation took yet another twist.

Greg McElroy has a concussion — which he didn’t reveal until Thursday — and will be replaced by Mark Sanchez as the New York Jets’ starting quarterback in the season finale at Buffalo on Sunday.

Coach Rex Ryan walked into his news conference before practice, took the podium and opened with: “You’re not going to believe this.”

McElroy, preparing to make his second NFL start in place of the benched Sanchez, was lifting weights Thursday morning and started experiencing headaches, Ryan said. McElroy went to the team’s training staff and then revealed he was suffering concussion-like symptoms after being sacked 11 times in the Jets’ 27-17 loss to San Diego last Sunday.

McElroy and head trainer John Mellody then went to Ryan to tell the coach the news. Ryan was not certain exactly when McElroy suffered the concussion.

“We come to find out that Greg wasn’t exactly truthful with our training staff after the game,” said Ryan, who acknowledged he was “stunned” to hear it. “He never disclosed that he had symptoms after the game to our trainers. Right now, he’s being evaluated for a concussion.”

Ryan said there was no way he would play McElroy against the Bills and the third-stringer will “definitely be out.” McElroy had been listed on the injury report Wednesday with a mild abdominal strain, but was a full participant in practice and was expected to play without any issues.

“I admire his courage and everything else, but you have to be truthful and I think that’s the lesson learned here with the medical staff,” said Ryan, who added he would speak to the entire team about concussions after practice. “The fact he really wanted to play, I understand the competitive side of Greg and all that, but the most important thing is the health of the players.

“Obviously, I feel fortunate that something like this showed up without him going out there and putting himself in harm’s way.”

Ryan chose to start Sanchez over Tim Tebow because the team has just two practices and a walkthrough to prepare before the game.

Sherman wins appeal

Seattle Seahawks cornerback Richard Sherman won his appeal of a four-game suspension for use of performance enhancing substances on Thursday, making him eligible for the NFL playoffs.

Sherman posted “I won,” on his Twitter account Thursday morning, followed by teammates tweeting their congratulations. Sherman added, “Thank you @nfl for upholding the truth! To the 12s Thank you your faith is rewarded! Thank you lord.”

The decision was made by former NFL executive Bob Wallace.

Sherman was steadfast since news broke of his pending suspension that he believed he would win on appeal. Sherman’s appeal was based on errors in the chain of custody of his sample and that there were mistakes made by the tester.

NFL spokesman Greg Aiello said in an email the league is reviewing the decision, but was declining comment due to confidentiality provisions.

The decision makes Sherman eligible for the Seahawks season finale against St. Louis and, more importantly, the playoffs. Seattle has played the last three weeks without fellow starting cornerback Brandon Browner who is serving a four-game suspension for a banned substance violation.

Browner’s suspension expires after Sunday’s game.

Around the league

All-Pro tackle Justin Smith of the San Francisco 49ers is unlikely to play Sunday in the regular-season finale against Arizona because of a partially torn left triceps. The injury could force Smith to miss some or all of the postseason. … Running back Steven Jackson will have the option to explore free agency after the season, raising the question of whether Sunday’s finale at Seattle will be his final game in a St. Louis Rams uniform. Jackson intimated Thursday that he might retire at the end of this season. … Dallas Cowboys nose tackle Josh Brent was driving with a suspended license and had a blood-alcohol content of 0.189 at the time of the car crash that killed teammate and friend Jerry Brown, according to documents released by police.