INDIANAPOLIS — Anthony Richardson is back, but it’s anyone’s guess the status of his offensive line when the Indianapolis Colts meet the Los Angeles Rams Sunday at Lucas Oil Stadium.

While Richardson worked his way through the NFL’s concussion protocol – he was a full participant all week – Pro Bowl center Ryan Kelly was unable to gain medical clearance after practicing Wednesday and Thursday. He won’t play Sunday.

Complicating matters for the offensive line: left tackle Bernhard Raimann is in the league’s concussion protocol after reporting symptoms following a practice. He was a full participant Wednesday and Thursday but did not practice Friday.

Also, right tackle Braden Smith had a brace/wrap on his right wrist and did not practice Friday. However, he doesn’t have a game-day designation, which is an indication he will play.

Richardson’s return, though, represents a major boost. He missed the 22-19 overtime win at Baltimore after sustaining a concussion in the week 2 win at Houston.

“He came back good; like he was the first two weeks,’’ Shane Steichen said. “He had a great week of practice, great week of preparation and I’m excited to get him out there on Sunday.’’

Richardson was on the sideline for the win over the Ravens, and admitted “it was a little rough for me.

“I was on the sideline, can’t throw a football, can’t go out there around the team,’’ he said. “It was eating me up inside. I’m excited to be back throwing the ball with the guys, bringing the energy back into the locker room. I’m excited to be back. I’m ready to play.’’

The No. 4 overall pick in the draft has missed one game entirely and failed to finish the other two because of injuries. The concussion sent him to the sidelines in the first quarter at Houston while a bruised left knee forced him to miss the final minutes of the opening loss to Jacksonville.

Richardson has admitted he’s got to do whatever’s necessary to protect himself when he’s either scrambling away from the pass rush or running on a designed play. But he isn’t preoccupied with the early injuries.

“No, it’s ball. The injuries I’ve got so far, nothing is crazy. I banged my knee on the turf. Everybody gets hurt on turf,” he said. “Then hit my head on the ground. That’s part of ball. I’m not going to change the way I play. I think I’m smart enough to know when to get down, when not to get down. Hopefully I can stay healthy the rest of the season.’’

Richardson sustained the concussion when Houston safety M.J. Stewart hit him as he was crossing the goal line on a 15-yard touchdown run in the first quarter. The play unfolded as the Colts expected, but Richardson was surprised Stewart closed as quickly as he did.

“I just thought it was an easy walk-in touchdown and I was just trying to trot in there,’’ he said. “Then guy’s closing fast and I tried to brace for it. The way I turned my body, just flopped back and hit my head and that was that.’’

Richardson experienced a headache immediately after the play and talked with the team about it. He opted to stay in the game for two more series before approaching the medical staff.

“I noticed I wasn’t feeling the way I should, so I asked them to take me to the tent,’’ he said. “I didn’t want to hurt the team.’’

Richardson’s third start of the season will require an adjustment on his part. He’ll be without his left tackle (Raimann) and center (Kelly).

And that patchwork offensive line will have to deal with a Rams’ defense led by tackle Aaron Donald, one of only three players in NFL history to be named Defensive Player of the Year.

“We’re working through it right now as a staff obviously,’’ Steichen said.

With Kelly out, Wesley French will make his second career start at center.

Either rookie Blake Freeland or Arlington Hambright probably will step in for Raimann at left tackle.

Freeland, a fourth-round draft pick in April, worked at both tackle spots during the preseason but has yet to step on the field with the offense in three games. He’s taken eight special teams’ snaps in two games.

Hambright started one of nine games with the Chicago Bears in 2020, at guard.

More on Kelly

Kelly’s situation bears monitoring. He suffered a concussion in week 12 of the 2017 season and wouldn’t return. He was inactive in weeks 13-15, then placed on the injured reserve list.

More medical issues

Three Colts are questionable for the game: left guard Quenton Nelson (toe), defensive tackle DeForest Buckner (groin/back) and quarterback Sam Ehlinger (right shoulder).

Nelson returned to practice Friday after missing the two previous days. That was his routine leading up to the Baltimore game.

You can follow Mike Chappell on Twitter at @mchappell51.