Jennings of the 49ers throws a punch at Mohrig after a cheap shot in a win over the Panthers.

SANTA CLARA, Calif. — San Francisco receiver Juan Jennings responded to a cheap shot from Carolina safety Trayvon Mohrig late in Monday night’s game by throwing a punch after the final whistle.

Television cameras caught Mohrig delivering a punch to Jennings’ gray area late in the 49ers’ 20-9 win over the Panthers. Jennings responded by walking up to Mohrig after the game and punching him in the helmet before punching him.

Jennings then needed to put the teams back before leaving the field.

“I’m just responding to some childish behavior,” Jennings said.

Mohrig said his shot at Jennings was in response to physical play after whistles and trash talk throughout the game. He admitted that he would likely be punished for his actions.

“He was pushing me back and stuff, so, you know. That was really all,” Mohrig said. “There’s really not much to it. It was just, you know what I’m saying? Like I said, I’ll take it. He wants to do something a little dirty, so … that’s who the man is.”

Jennings has a history of physical play with his aggressive blocking and running style. That led to him being ejected after a scuffle with Arizona cornerback Sean Murphy-Bunting in last season’s finale and now a run-in with Mohrig.

But Jennings said he was surprised by how Mohrig reacted, with a blow to a sensitive area.

“It was just out of nowhere,” Jennings said. “Maybe it’s just my history of playing ball. I play hard. I’m physically stronger than a lot of DBs. At least I have a lot going on between the whistles.”

San Francisco coach Clay Shanahan called Mohrig’s actions a “slow shot” and was glad there wasn’t a bigger reaction from Jennings.

“I was proud of John for not losing his mind there and going to the sideline,” Shanahan said.

Carolina coach Dave Canales said he wanted to talk to Mohrig about what happened.

“I’ll get to the bottom of it,” he said. “I want to see what really happened. I haven’t had a chance to talk to Trey about it yet. That’s going to be a conversation I’ll dig into. … I’ll get a chance to watch the film right now and see what happened.”

The NFL is likely to fine both players and possibly more. Detroit’s Brian Branch was suspended for one game earlier this season after hitting Kansas City receiver JoJo Smith-Schuster after the game ended.