Offensive tackle Joe Staley will try to return to 49ers practice Wednesday and has an “outside chance” of playing in Sunday’s game against Carolina, head coach Kyle Shanahan said Monday.

Staley, a team captain and six-time Pro Bowl selection, sustained a broken left fibula Sept. 15 against Cincinnati. Shanahan had been hoping Staley might return for the Thursday night game at Arizona on Oct. 31, but now it’s possible he could rejoin the lineup four days earlier.

“I think he’s going to try to get out there and practice a little bit this week,” Shanahan said of Staley. “We’ll see how it goes over these next two days. We’ll see how he feels on Wednesday.

“I do think there’s an outside chance (for Sunday’s game). ... Hopefully we can get him on the practice field and he feels good.”

Staley went through an extended pregame workout on the field Sunday in Washington before San Francisco’s 9-0 victory. Staley moved well during his workout, which included short sprints; he did shake his left leg a few times while going through pass-protection sets.

Justin Skule has played respectably at left tackle in Staley’s absence. Mike McGlinchey, the usual starter at right tackle, also is sidelined by a knee injury.

One other injury update: Shanahan said cornerback Ahkello Witherspoon (foot), who had a setback last week and missed the game in Washington, probably will not be ready for Sunday’s game.

Garoppolo’s so-so 16: It took six seasons, but quarterback Jimmy Garoppolo finally did it: He now has a season’s worth of starts.

Garoppolo made his 16th career start Sunday, when he threw for a career-low 151 yards and rushed for a career-high 20 yards.

So what does a full season of Garoppolo look like? Well, statistically speaking, it looks utterly average. Based on 2018 NFL passing numbers, Garoppolo’s stats in his 16 starts would have ranked him between 14th and 17th in most major categories.

However, there are two notable exceptions. Garoppolo’s 14 interceptions would have tied him for the fifth-most in the league. And his 14 wins — yes, he has a 14-2 career record as a starter — would rank first.

Ron Kroichick and Eric Branch are San Francisco Chronicle staff writers. Email: rkroichick@sfchronicle.com, ebranch@sfchronicle.com Twitter: @ronkroichick, @Eric_Branch