SANTA CLARA, Calif. -- While the San Francisco 49ers have been ravaged by injury in the opening weeks of the season, they had mostly avoided the big, season-ending type of ailments. Until Sunday.

Defensive tackle Javon Hargrave suffered a partially torn right triceps in Sunday's loss to the Los Angeles Rams, an injury that will require surgery and is likely to bring his 2024 season to an end.

"It's a big [loss]," coach Kyle Shanahan said. "I thought he had his best game yesterday. I thought he was a huge factor, really affected the quarterback in that game. ... He's one of our better players. He was definitely going in the right direction and was going to have a big year."

Hargrave wasn't the only injury update of note from Shanahan on Monday. Quarterback Brock Purdy came out of the game with back soreness and though an MRI came back clean, he will be day-to-day this week, according to Shanahan.

In addition, running back Christian McCaffrey flew to Germany over the weekend to visit with a specialist about the persistent Achilles tendonitis that landed him on injured reserve Sept. 14, Shanahan said.

After the loss to the Rams, Shanahan and the Niners were hopeful that Hargrave was just dealing with a bruised triceps. Further imaging revealed the tear Monday, leaving Hargrave in need of a repair. Through three games this season, Hargrave had seven tackles and a sack.

With Hargrave out, the Niners are likely to look in-house for his replacement, with Shanahan pointing to the practice squad where Evan Anderson or T.Y. McGill are possible options to be promoted to the roster.

Kevin Givens or Jordan Elliott are the possibilities on the active roster to step into a starting role with end Yetur Gross-Matos capable of moving inside on passing downs. Kalia Davis, who is on injured reserve with a knee injury, is also close to returning, Shanahan said, though that isn't expected to happen this week.

Shanahan also indicated there's an outside chance Hargrave could return but acknowledged the Niners would need to make a deep postseason run for that to be possible.

"When you get surgery that's usually a few months at least," Shanahan said. "If there was a chance, it would have to be late in the playoffs."

McCaffrey's trip to Germany comes a little more than a week after the Niners placed him on injured reserve. Shanahan first announced that McCaffrey was dealing with a calf injury Aug. 6. That ailment kept McCaffrey out for the rest of training camp, but he returned to practice leading up to the Week 1 game against the New York Jets.

That week, Shanahan also revealed that McCaffrey was dealing with the Achilles issue and it was that, more so than the calf, that was bothering him. McCaffrey was then a surprise scratch against the Jets despite practicing on a limited basis and being listed as questionable before that game.

The following week, McCaffrey again took part in practice but had what Shanahan called his "worst day" Sept. 12. Shanahan acknowledged the next day that McCaffrey was a candidate for injured reserve and the team made that move official Sept. 14.

Because he's on injured reserve, McCaffrey must miss four games before he's eligible to practice or play again. He's missed two games already but must sit out at least next week's game against the New England Patriots and the Oct. 6 game against the Arizona Cardinals.

The earliest McCaffrey could return would be Oct. 10 at the Seattle Seahawks, though Shanahan has said "nobody knows" when he will actually be back because of unpredictable nature of his injury.

McCaffrey isn't the first athlete to travel abroad to deal with injury. Kobe Bryant, Tiger Woods and others have gone to Germany for treatment over the years.

"I'm not sure what doctor it is," Shanahan said. "I know he's going to see a specialist that he believes can help him with his Achilles process and I think he's doing that over these next few days. Hopefully it will help."

The injury news wasn't all bad for the Niners on Monday. Shanahan said the Niners are hoping to get tight end George Kittle, who missed Sunday's game with a hamstring injury, back to practice this week and cornerback Charvarius Ward (knee, hamstring) is "good to go."

After having good injury luck in their Super Bowl run last year, the Niners have been hit much harder so far this season.

"Last year just with some of our main guys, we were very fortunate they didn't miss too many games," Shanahan said. "This year has been totally different to start out so that's been really tough. I try to stay positive with it that all of them are eventually going to come back, but that probably changed with Hargrave today so that was a tough pill to swallow there. But we definitely haven't had the luck that we had last year."