A visibly worked-up Eric Reid had to be held back by teammates, including former Eagles receiver Torrey Smith, after tensions flared up during pregame workouts ahead of the Eagles' game against the Panthers on Sunday.

>> READ MORE: Eagles vs. Panthers: Live updates

It's unclear what lead to the incident, but during the flare-up, the safety was seen jawing with Eagles safety Malcolm Jenkins.

"That has the feeling of something that is outside of the game today," Fox analyst Charles Davis during the game's broadcast.

During a play in the first quarter, Reid was penalized after tackling quarterback Carson Wentz well after Wentz handed off the ball. The penalty was offset by another personal foul also called on the play after Eagles tight end Zach Ertz came to Wentz's defense after the play.

"The ball's long gone and he's tacking their quarterback," Davis said. "There's going to be a confrontation when that happens."

During the beginning of the second quarter, Reid delivered a forceful hit on Ertz after he pulled down a 21-yard reception. Eagles fans in the stadium groaned when there was no penalty called, but according to retired NFL official Ed Hochuli (who is offering live rules clarifications online today for the NFL), it was a clean hit.

The bad blood between Reid and Jenkins goes back to last season, when Reid was still with the San Francisco 49ers. Reid left The Players Coalition, which was founded by Jenkins and Anquan Boldin, over disagreements Reid had with the Eagles safety.

Earlier this year, Reid told reporter he thought The Players Coalition was "an NFL funded subversion group.Reid told ESPN last year that Jenkins informed the NFL that players would stop protesting during the national anthem if the league donated money to certain initiatives, something Reid said he was left in the dark about.

"I feel like I've been misled," Reid said. "I won't accuse Malcolm of directly lying to me, because I don't think he's that type of guy. But I will say he's misled us. And shoot, if that's what lying is, then that's what it is."

At the time, Jenkins said he was surprised by Reid's decision.

"We were discussing some of the details of what the league has proposed. I wanted some input," Jenkins told my colleague Bob Brookover. "Really that was the biggest thing. I was asking for some input before I responded to some of the questions that the league had from us. So, yeah, this did catch me by a little bit of a surprise this morning."

Kevin Burkhardt, who is handling play-by-play duties on today's game for Fox, said he spoke with Jenkins about Reid during the network's interviews prior to the game.

"[Jenkins] said, 'I'm happy Eric is back in the league. I am proud of what he has stood for,' " Burkhardt said.

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