Joe Burrow had already taken a lot of hits Sunday. The Cincinnati Bengals haven’t protected their rookie quarterback all that well.

The worst fear of Bengals fans happened in the third quarter at the Washington Football Team when Burrow took a hit he didn’t get up from. Burrow went down and was loaded on a cart as teammates patted him on the helmet. It appeared to be an injury to his left leg, possibly his knee. Ryan Finley came in the game for the Bengals.

Burrow tweeted a grim early diagnosis, saying, “Thanks for all the love. Can’t get rid of me that easy. See ya next year.”

According to NFL Network’s Ian Rapoport, Burrow suffered a torn ACL with the possibility of additional damage.

The No 1 overall pick out of LSU had played fantastically this season, especially considering he was behind a bad offensive line. If the injury keeps Burrow out a while, it will end a promising rookie season. Hopefully it doesn’t carry over to the start of next season if it’s serious.

Players on both sides reacted like it was a serious injury, coming over to give their well wishes.

Burrow was throwing when a Washington defender rolled into his left leg, causing it to buckle:

The loss is a huge blow for the Bengals, of course, but also the NFL as a whole if Burrow misses any significant time. He was one of the NFL’s best stories, as his great season at LSU carried over to the pros immediately. The Bengals haven’t been very good around him but he was still a bright spot, for this season and the future.

More from Yahoo Sports:

• Thamel: Somehow win makes season for Harbaugh, Michigan worse

• Goodwill: Pelinka’s ego not getting in way of LeBron building Lakers

• What will first set of College Football Playoff rankings look like?

• Haynes sources: Longtime Cav Thompson agrees to deal with Celtics