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

Richardson suffered an oblique injury in last week's 27-24 win against the Pittsburgh Steelers after colliding with a defender at high speed. He indicated Wednesday that his injury, which was effectively a deep bruise, improved significantly in the days after the first hit. But the Colts made slow progress on Richardson in practice this week, with the quarterback making only occasional throws in individual drills during portions of practice open to the media.

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

The injury will likely force veteran backup Joe Flacco into action, a week after he came into the game and secured the win over Pittsburgh. Flacco would be in the starting lineup for the first time since playing in Cleveland last season, a scenario he said is easier than coming off the bench like he did a week ago. The more intense preparation Flacco received in recent days while Richardson was primarily a spectator made him better prepared, Flacco said.

“You can’t really understand the difference until you’ve had to do it both ways,” he said. “…I just call the game every day. We just did a tour “are) 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 would be of less help on Sunday as the Colts' injuries extend far beyond Richardson.

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

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

The Jaguars, meanwhile, received good news on Saturday as defensive end Josh Hines-Allen cleared concussion protocol and will play on Sunday. It is questionable whether tight end Evan Engram will be able to play because of a hamstring injury that has sidelined him since Week 1, and he does not plan to play on Sunday, sources told ESPN's Jeremy Fowler.

As for Richardson, his recent injury has sparked renewed discussion about his endurance. He struggled a bit earlier this week, suggesting the injury shouldn't be surprising given the blow he sustained.

Regarding fans' criticism, Richardson said: “It's football. I'm pretty sure if (fans) leave the house and come here and get hit by someone who runs over 20 miles an hour every week, I'm pretty sure. “They're going to be in pain and with injuries too have to fight. 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 being named the NFL's No. 4 draft pick in 2023. In Week 5 of his rookie season, he suffered a shoulder injury that required surgery and ended the season.

He also missed a game last season due to a concussion.

Richardson has struggled with turnovers this season and threw 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).