San Francisco 49ers running back Jerick McKinnon has suffered another setback according to general manager John Lynch. According to Tom Pelissero of NFL Network, the injury is considered a flare-up with his surgically repaired knee.

McKinnon returned to the practice for the first time yesterday in 18 days after undergoing treatment on his knee. This all stems from a torn ACL that he suffered on September 1st, 2018 but instead of making solid progress it has been setback after setback.

Lynch said in a radio interview that he didn't have a lot of information on the setback, but did call the situation a “real bummer.”

“Because the situation is up in the air, I'm not going to say a whole lot,” Lynch said on the “Murph and Mac” show via 49erswebzone.com. “I can tell you that again, yesterday (Tuesday), we brought him out, and it's a real bummer because he keeps getting to the final step. And the final step is actually playing NFL football, particularly at his position where you've got to make hard cuts, you've got to put your foot in the ground.

“We did it a month ago, and we got to that step, and he kind of regressed. And I would say yesterday, we had a similar situation. So we're trying to get to really what's the root cause of the problems that he's having.”

Hopefully, it turns out that this is just a minor setback and he will be back on the field soon, but judging by Lynch's comments, that isn't the case.