Indianapolis Colts quarterback Anthony Richardson's status for Sunday's game has been downgraded to doubtful, making it unlikely the second-year player suits up against the Jacksonville Jaguars.

Richardson suffered an oblique injury after a high-speed collision with a defender in last week's 27-24 win over the Pittsburgh Steelers. He indicated on Wednesday that his injury, effectively a deep bruise, was feeling considerably better in the days following the initial hit. But the Colts brought Richardson along slowly in practices this week, with the quarterback executing only casual throws in individual drills during the portions of practice open to media.

Richardson was listed as a limited practice participant on Wednesday, Thursday and Friday.

The injury will likely press veteran backup Joe Flacco into action, one week after he entered the game and preserved the win over Pittsburgh. Flacco would be making his first start since his late-season run in Cleveland last season, a scenario he said is easier than coming off the bench as he did a week ago. The more intense preparation Flacco got in recent days, while Richardson was mostly a spectator, has him more prepared, Flacco said.

"You really can't grasp the difference until you've had to do it both ways," he said. "... Just calling the play on a daily basis. We just did a walk-through. I got to call all the plays. And you go have practice, you get to call the plays. That little bit right there, [you're] much more familiar with the game plan."

Flacco completed 16 of 26 pass attempts for 168 yards and two touchdowns against Pittsburgh without throwing an interception. But he'll have less help on Sunday if he finds himself playing again. The Colts' injuries for this game extend well beyond Richardson.

Center Ryan Kelly (neck) has also been downgraded to doubtful and could miss his second consecutive game. Additionally, star running back Jonathan Taylor has already been ruled out with an ankle sprain.

Defensive end Tyquan Lewis was placed on injured reserve on Tuesday with an elbow injury, and cornerback Kenny Moore II (hip) will miss his second straight game.

As for Richardson, his latest injury has caused conversations about his durability to resurface. He pushed back a bit earlier this week, suggesting the injury should not be surprising given the hit he took.

Regarding criticisms from fans, Richardson said, "It's football. I'm pretty sure if [fans] got out the house and came out here and got hit by somebody that's running 20-plus miles per hour every week, I'm pretty sure they'll be sore, dealing with injuries as well. So, people are going to talk. That's what people do and I'm not necessarily worried.

"I'm just trying to focus on getting better."

Richardson has missed 13 of a possible 21 games since becoming the NFL's No. 4 draft pick in 2023. He suffered a shoulder injury in Week 5 of his rookie season that required surgery and proved season-ending.

He also missed a game last season with a concussion.

Richardson has struggled with turnovers this season, throwing six interceptions. But he also ranks third in the NFL in yards per attempt (8.5) and is first in air yards per attempt (12.6).