Even as the situation practically begged for a quarterback change, Romeo Crennel stood by his man. Matt Cassel was involved in all four of the Chiefs’ turnovers Sunday, but Crennel refused to make the switch to Brady Quinn.

Finally, in the fourth quarter of what would be a 9-6 loss to Baltimore at Arrowhead Stadium, the Ravens made the decision for Crennel. Raven defenders Haloti Ngata and Paul Kruger hit Cassel as he threw a pass, knocking him out with what appeared to be a concussion.

Barring an unforeseen and quick turnaround for Cassel, the Quinn era will begin for the Chiefs with next week’s game at Tampa Bay. Even Crennel, who coached Quinn for two seasons when they were together with the Cleveland Browns, wasn’t certain what that would mean for the Chiefs.

“We’ll find out,’’ Crennel said. “If he is the quarterback, we’ll put him in there and play him. I was pleased with what he did today in the time that he got in because he hasn’t had many practice reps. I thought he did a nice job when he went in.’’

With the Chiefs down 9-3 when he replaced Cassel, Quinn almost led a comeback. He had a touchdown pass to Dwayne Bowe called back when Dexter McCluster was penalized for pass interference.

The Chiefs settled for a field goal on that drive, and they never got the ball back. But in his short time on the field, a stint that consisted of his eight snaps, Quinn threw perhaps Kansas City’s best pass of the day, a bullet to Bowe for 20 yards on third down to allow the Chiefs to continue their drive.

Though Cassel could at some point return, the Chiefs are looking at a second straight season with at least some games without him. He broke his hand in the season’s ninth game last year and didn’t return.

“You can’t escape things like this in football,’’ McCluster said. “It’s a contact sport. The next guy always has to be ready, and Brady prepares himself like he’s going to play every week. We’re hoping for a speedy recovery from Matt but for right now, (Quinn) is all we have. If he has to step up to be the man, I’m pretty sure he’s going to be ready.

“It’s like we didn’t miss a beat. He came in and he came in poised. You want that type of leadership from your quarterback. We moved the ball. We showed we can move the ball.’’

Perhaps Crennel’s thoughts on Quinn are revealed by the fact he’s stuck with Cassel through so much. Cassel was officially on Sunday given one fumble to go along with his two interceptions, though his fumble of the snap on the goal line that appeared to cost the Chiefs a certain touchdown was given instead to center Ryan Lilja.

That makes 13 turnovers for him in five games. Yet Crennel had no serious thoughts of pulling him in favor of Quinn.

“I did not,’’ Crennel said. “I went with my team, and my team played pretty good football, just not good enough to win.’’

Quinn’s thoughts as he replaced Cassel went to the last time he played in a regular season game. That was 2009, when he played for Cleveland, and it also was at Arrowhead Stadium.

The Browns beat the Chiefs that day and Quinn injured his foot, ending his season. Since then, he had two seasons with the Broncos in Denver, where he never got in a game but had a front row seat for all the drama involving Tim Tebow and Kyle Orton.

“It felt great to be out there (again),’’ Quinn said. “I felt comfortable being out there on the field, being at home.

“It’s part of the job. Obviously, it’s different considering you don’t get to practice as much (and) you’re not physically prepared. I try to keep myself as prepared as possible and doing as much extra stuff as I can, whether it’s at our facility or at home trying to prepare myself for that moment.’’