SANTA CLARA – Kyle Shanahan certainly relates how the Indianapolis Colts, down to a third-string quarterback, summoned Philip Rivers out of retirement.

Shanahan and the 49ers nearly took the same path three years ago.

Their December 2022 pursuit of Rivers came in the wake of injuries to Trey Lance and Jimmy Garoppolo, and before Brock Purdy shed his “Mr. Irrelevant” novelty role.

“We talked to Philip as soon as Jimmy broke his foot (Dec. 4, 2022) and talked about the possibility of him coming in,” Shanahan said Wednesday. “I remember telling him that we really felt good about this rookie that we had. … We had no backup and we also had a rookie who was the last pick of the draft and hadn’t played a snap except yet for mop-up time. So we’re not sure where this is going to go. But we’d like to see him go and see how he can do, because we think he might do real well.”

Before the 49ers (9-4) visit the Colts and Rivers for a Monday night matchup Dec. 22, the Tennessee Titans (2-11) come Sunday to Levi’s Stadium.

Still, Wednesday’s NFL-wide storyline was how Rivers, 44, is reviving a career that’s already made him a Pro Football Hall of Fame semifinalist for the Class of 2026.

Can Purdy, 25, envision himself still playing in 20 years? “Hope so,” said Purdy, noting he’s as curious as anyone how Rivers’ comeback will go.

Rivers ranks among the NFL’s top-10 passers of all-time (attempts, completions, yards, touchdowns). Three years ago, he was boning up on the 49ers’ scheme for a bullpen call that never came, as Purdy led the 49ers to the NFC Championship Game.

“When he plays, he’s one of the best quarterbacks of all time,” Shanahan said. “As you get older, mobility leaves big-time, but arm strength doesn’t always.” (Shanahan has openly discussed in previous years the 49ers’ courtship of Rivers.)

Left tackle Trent Williams, 37, has stated how he wants to play into his 40s, so he’s understandably excited to see Rivers return to the NFL arena, albeit after a five-year hiatus.

“It gives some hope to the older guys that we’ll still be doing it around that age,” Williams said. “I’ve been a big fan of Philip for a long time, so I’m happy to see him back, would love to see him out there just for the league.”

Hall of Famer Patrick Willis, who’s a decade into retirement, isn’t angling for a Rivers-esque return even though the 49ers are down to a third-string middle linebacker, with Fred Warner (Injured Reserve) and Tatum Bethune sidelined by ankle injuries.

But Willis probably shares the same mindset as Rivers in one sense. “There’s not a moment or time where I’ve not felt, ‘You know what, I think I can still whoop these cats’ (butts) or whatnot,’ but I just don’t have to,” Willis told this news organization Wednesday. “Where I came from, the South, the old heads would say, ‘I might be older but I’ve still got it.’ ”

What Willis now has are healthy toes, after chronic pain ended his eight-year career. “That was part of the reason why I made the decision (to retire) then, so I could feel this way now,” Willis added.

INJURY UPDATES

Bethune (ankle), defensive end Sam Okuayinonu (ankle) and linebacker Nick Martin (concussion) have not been cleared to practice. Fullback Kyle Juszczyk, who injured ribs in the Nov. 30 win at Cleveland, participated in a limited capacity.

Defensive lineman Yetur Gross-Matos (hamstring) is expected to resume practicing Thursday, opening a three-week window for the 49ers to activate him off Injured Reserve.

PINEIRO RETURNS

Kicker Eddy Piñeiro is back after not kicking for almost two weeks because of a hamstring strain, which occured on his final point-after kick in the Nov. 16 win over Arizona.

“It wasn’t a crazy injury so I knew I had a good shot and the training staff did a great job to get me back,” said Piñeiro, noting it was frustrating to miss his first games in almost four years.