The Colts will be without Ryan Kelly for at least the next four weeks, as the veteran center was placed on injured reserve Tuesday with a knee injury.

Kelly will have a chance to return again this season, head coach Shane Steichen said on Wednesday, and the Colts will miss Kelly's veteran presence while he's on injured reserve. But the Colts will also move forward confident in rookie Tanor Bortolini's ability to take his place on the offensive line.

"Obviously, been doing at a high level – team captain for us, great leadership," Steichen said of Kelly. "Been doing it for a long time. So, anytime you lose a guy like that, it's tough, but we're excited for Tanor's opportunity. When he's had to play, he's played well."

Bortolini, the 2024 fourth-round pick from Wisconsin, will re-enter the starting lineup after starting in place of Kelly in Weeks 4 and 5; he also played 23 snaps in Week 6 – the entire fourth quarter of the Colts' comeback victory – in relief of Kelly against the Tennessee Titans.

Through those three games, Bortolini earned a 66.3 Pro Football Focus overall grade (15th among centers with 150+ snaps) with a 77.3 PFF pass block grade (third among centers with 150+ snaps). Among rookie offensive linemen, Bortolini has the highest PFF pass block grade this season:

"He plays physical," Steichen said. "Obviously, when he got his opportunity during the year, he did a hell of a job. So, excited for his toughness. Really smart, cerebral player, sees the game well – so it should be good."

Bortolini got his first NFL start in Week 4 against a Pittsburgh Steelers front that features a potential Hall of Fame defensive tackle in Cameron Heyward, who's a three-time first-team AP All-Pro with 83.5 sacks and 125 tackles for a loss in his 14-year career. Getting to go against Heyward and that Steelers line provided a valuable growth opportunity for the 22-year-old Bortolini.

"The good news is when you play in a game against really good players from different teams, it's different than going against the guys you go against every day in practice, so it gives you something to work on," Bortolini said. "If they beat you, it sucks to get beat obviously, but it's a good learning experience. Like, okay, how did they beat me, what did I do, and what can I control next time to make sure that doesn't happen again."

Bortolini, too, has primarily worked with veteran Joe Flacco, beginning in training camp with the Colts' second-team offense and then for all but a handful of his snaps at center this regular season. Flacco's experience has helped Bortolini in making the right calls when the offense gets to the line of scrimmage, a critical part of playing center in the NFL.

"The good thing about having Joe back there is he's someone that's played a ton of football, so he sees things that I don't see or haven't seen yet because he's had all this reps, all that time," Bortolini said. "It's really great to be paired up with somebody — he's able to help a young guy along the way. You have a veteran quarterback and a rookie center. I think there's probably not a bigger age gap in the NFL between the two. But it's good to have a guy like that I can lean on, and if I have any questions I'm able to ask, he's able to help out."

Bortolini was right, by the way: The age gap between him and Flacco is 17 years, five months and two days, narrowly edging out the 17-year, three-month, 22-day gap between 40-year-old New York Jets quarterback Aaron Rodgers and 23-year-old center Joe Tippmann.

"We've already had a few games this year where we've had to have him specifically step up at center," Flacco said. "And I think any experience is good. The fact that he's had real time game action I think is a huge positive for our O-line."

Thursday's practice report: