Vikings starting left guard Brandon Fusco, who on Friday was a full participant in practice but was still going through the NFL's concussion protocol, has been listed as questionable for Sunday's game against the San Diego Chargers.
If Fusco is not cleared to play, the Vikings could turn to Jeremiah Sirles, who was acquired three weeks ago in a trade with the Chargers.
"It would be kind of fun to play against the team you started with," Sirles said.
Sirles signed with the Chargers last spring after going undrafted out of Nebraska. He ended up making the team, starting one game and playing in another.
"If you're not a starter, you have to prepare like a starter because you never know when your number is going to be called," Sirles said. "That happened to me last year. [I was a] backup and all of the sudden the guy went down and you kind of get thrown in there."
Coach Mike Zimmer said Sirles has practiced at three positions on the line since arriving. "He's a big guy, keeps his feet moving, [is] athletic. He's got some toughness to him," Zimmer said.
Sirles lined up at Fusco's left guard spot Wednesday. Fusco returned to practice Thursday.
Rookie Austin Shepherd and second-year lineman Zac Kerin are the other candidates from the active roster to start if Fusco is unable to play.