Deebo Samuel, Trent Williams day-to-day; 49ers optimistic on Christian McCaffrey

SANTA CLARA, Calif. -- One day after three of their most important players left their loss to the Cleveland Browns with various ailments, the San Francisco 49ers seemingly got some good news on the injury front.

On Monday afternoon, Niners coach Kyle Shanahan offered updates on injured receiver Deebo Samuel (shoulder), running back Christian McCaffrey (oblique/rib) and left tackle Trent Williams (right ankle). While the 49ers are awaiting additional imaging on McCaffrey, Shanahan sounded optimistic on all three situations.

Shanahan said Samuel and Williams would be "day-to-day" this week as the 49ers prepare for Monday night's trip to Minnesota to play the Vikings. That comes after Samuel departed in the first quarter Sunday with a shoulder injury and did not return while Williams gritted through the game after spraining his ankle with 3:14 left in the opening quarter.

Shanahan said Williams' injury is not a high ankle sprain. McCaffrey's situation seems a bit more tenuous, as the Niners await further information before offering a diagnosis and a timeline to return. Asked whether McCaffrey could be in position to play through the injury with the use of a flak jacket, Shanahan said he wasn't sure.

"It's obviously a tougher position just because you get hit a lot more," Shanahan said. "But we've just got to see how it reacts. We've got to see exactly what's wrong with it too because we haven't got that back yet. We say oblique/rib, hopefully it's not both, but we've got to wait to see for sure."

On Sunday, it was unclear when exactly Samuel and McCaffrey got injured, but Shanahan offered some clarity on that as well. Samuel's shoulder injury came on the first play from scrimmage, an 8-yard run by him on a jet sweep.

"He just took a shot on the shoulder," Shanahan said. "It didn't look overly big or anything. It just connected right. And so it got him after that. And if you watch him like the next eight plays, you could just tell the feeling was starting to go because he couldn't use his left arm. [He] tried to come back but just couldn't get feeling back in it. So we had to shut him down."

McCaffrey left the game in the third quarter but returned for one play -- a 6-yard run with just under three minutes left in the quarter -- before heading to the sideline and then the locker room. The Niners ruled out his return with 10:58 to play. The in and out made it harder to nail down when McCaffrey's injury occurred.

"He mentioned about four possible plays he thought he could have done it on," Shanahan said. "But we're not sure which one he did."

With McCaffrey out Sunday, the Niners turned to the combination of Elijah Mitchell and Jordan Mason in his place. Mitchell, in his first game back from a knee injury, had two carries for negative-3 yards. Mason had five attempts for 27 yards and a touchdown.

Shanahan indicated that Mason and Mitchell would both get opportunities if McCaffrey can't play against the Vikings. He also offered some optimism that McCaffrey could be available.

"Both of those guys have done very well," Shanahan said. "Elijah came back and practiced late last week on Thursday, so then he got really one true day of practice in and that's why JP got the first nod once Christian came out. But we've got two really good players there. And I know [running back Tyrion Davis-Price] is waiting for his opportunity also. Hopefully, Christian will be good to go this week, but if not we've got a group of backs we can rely on."

There was little doubt about when Williams sprained his ankle after a Browns defender rolled into the back of his leg. Williams missed two offensive snaps and returned to finish the game. After the loss, Williams said he wanted to play through the injury so the team and backup tackle Jaylon Moore wouldn't be put in a tough spot against Browns edge rusher Myles Garrett.

"Trent's a very intelligent guy who is also very competitive and understands what those decisions are," Shanahan said. "And he said he could come back. I wasn't expecting him because of how bad the injury looked. The trainers thought that it wasn't as serious as it looked. Trent was adamant to get back out there and then we keep our eyes on him all game. ... That was a pretty courageous effort by him coming out and those circumstances, especially the player he was going against."

The 49ers are also expected to get linebacker Dre Greenlaw back in practice this week after he missed Sunday with a hamstring injury, Shanahan said.