49ers QB Jimmy Garoppolo (thumb) not expected to start vs. Texans, likely to undergo offseason surgery

49ers quarterback Jimmy Garoppolo's injury may have been kept quiet for a few days, but the thumb injury he suffered in a loss to the Titans was a significant one.

In fact, sources say that Garoppolo is expected to have surgery following the season to repair the torn ligament and chipped bone in the thumb on his throwing hand. In rare times, these types of injuries can heal on their own, but sources say this is not the type that can. He is expected to make a full recovery.

Garoppolo is listed as doubtful for Sunday versus the Texans after not practicing all week in practice, but coach Kyle Shanahan said Friday, "He's not out, so I'm holding out hope."

However, a source said Saturday that Jimmy G is, in fact, expected to be out with first-round rookie Trey Lance set to start. Lance took all the first-team reps, so this is no surprise.

The 49ers can clinch a playoff berth with a win and a New Orleans loss.

With Garoppolo not able to practice this week, the door has been opened to a real question for the immediate future: Will San Francisco's starting quarterback be able to play again this season?

A significant tear in the UCL in a quarterback's throwing thumb -- which Shanahan described as a Grade 3 sprain -- can essentially prevent a quarterback from gripping a football. Throwing can be painful and difficult. In fact, according to Shanahan, Jimmy G did not throw all week.

Whether that can get better with rehab but without surgery is a question that San Francisco may have to wrestle with for Week 18 and potentially into the playoffs. Garoppolo was optimistic early in the week that he would be able to go, but not improving enough to throw was not a good sign.

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