The San Francisco 49ers may be without their star running back for the remainder of this one. Christian McCaffrey left Sunday’s game against the Atlanta Falcons with a leg injury that the team has since described as a thigh injury, and he has been ruled questionable to return. 

It was also reported that McCaffrey has headed to the locker room. Since that report, McCaffrey has returned to the game against the Falcons.

The NFL on Fox broadcast pointed out that McCaffrey was getting worked on along the sideline after he exited. For a 49ers team that runs so much of its offense through No. 23, that is never a sight you want to see. McCaffrey has also been seen doing bike work and stretching on the sidelines after the start of the second half.

McCaffrey was doing it all before he went down

Before he left, McCaffrey was doing what he always does. He ran for 29 yards and a touchdown on the ground, and he caught three passes for 45 yards. Those 45 receiving yards lead the team in this one.

Think about that for a second. Your running back is also your leading receiver, and he got there before the game was over. That is the McCaffrey experience in a nutshell, and it is exactly why his health matters so much to this offense.

He is the engine. He keeps defenses honest in the run game, and he gives the quarterback a safety valve in the passing game who can turn a checkdown into a chunk play. When you take that guy off the field, everything else has to work a little bit harder.

Now, 29 rushing yards is not an eye-popping number on its own. But the touchdown and the production through the air tell you he was involved and effective, plus it was early in the game when he left. The Falcons had to account for him on every snap, and that opens things up for everybody else.

Kaelon Black and Jordan James are ready

Here is the good news for San Francisco. Rookie running back Kaelon Black already has a rushing touchdown of his own against Atlanta. The 49ers might have to lean on him and Jordan James more in this one.  

If McCaffrey cannot play as much in the second half, the 49ers are not handing the ball to a guy who has been sitting cold on the bench all afternoon. Black has already found the end zone, and he has already shown he can handle work in a game that counts.

Look, nobody is going to replace what McCaffrey brings to this offense. He is one of the most complete backs in the NFL. But a rookie who can come in and punch one in gives this team a real option, and I’m high on what that says about him. Young running backs earn trust by producing when their number gets called, and Black has done exactly that.

This could be a big opportunity for a first-year player in Kaelon Black, and it is a chance for him to show the coaching staff he can carry more of the load when this team needs it.

What comes next for the 49ers

It’s great to see McCaffrey return to the game, but it’s fairly obvious that he isn’t at 100%. Knowing how tough he is, he will likely gut it out the rest of the way to try to keep the 49ers undefeated record.

The bye week is coming up after this one against Atlanta wraps up, giving McCaffrey plenty of time to rest. The 49ers will get more clarity on McCaffrey once the medical staff evaluates him after the game, and that update will tell us a lot about how this backfield shapes up over the next few weeks.

I think Christian McCaffrey is going to be just fine, and this ends up being more of a light injury scare than anything else. And if he does need some time, Kaelon Black has already shown he can step in and make plays for San Francisco.