SANTA CLARA >> Josh Dobbs will start in place of the injured Brock Purdy when the last-place 49ers (6-10) close their season Sunday at the Arizona Cardinals (7-9).

Purdy was among several players not practicing Wednesday, having sustained an elbow contusion that caused nerve irritation with about 1 1/2 minutes remaining in Monday night’s 40-34 defeat to the Detroit Lions.

Purdy’s injury was to his surgically repaired throwing elbow, but it was not deemed a long-term issue by coach Kyle Shanahan. Purdy should slot back in as the starter once the offseason program begins in some 3 1/2 months, presuming he does not hold out for a contract extension that he’s eligible to receive at season’s end.

Dobbs will be the 49ers’ third different starting quarterback this season, and it’s the fifth time in eight seasons Shanahan has needed to deploy a starting trio, with only Jimmy Garoppolo starting every game in a season (2019) and Purdy skipping the 2023 regular-season finale out of precaution with the No. 1 seed intact.

Brandon Allen started over Dobbs in the Nov. 24 loss at Green Bay while Purdy sat out with a right shoulder injury.

Dobbs is slated to speak with the media today. Shanahan said of Dobbs’ practice work this season: “He’s been great, him and Brandon. I’ve looked at both of them as our (No.) 2 throughout the year. Both have given really good looks in the scout team. They split reps there, and they’re always ready.”

Once Purdy got injured Monday night, Dobbs came on for his 49ers’ debut, completed 3-of-4 passes (35 yards), and scored on a last-minute, 7-yard touchdown run.