Key players quietly leaving the field with injuries has become a disturbing theme of Patriots camp in the last week or so.

Monday, Rob Gronkowski became the latest victim.

About midway through the first joint practice with Chicago, the All-Pro tight end was running an out pattern in a 5-on-7 period. The pass intended for him sailed high over his head and out of bounds, but Gronkowski tried to jump for it anyway. As he came down, he let out a painful grunt and stayed out of bounds as he made his way slowly back to the huddle.

Gronkowski remained out of action for the next few plays. Eventually, a member of the medical staff came over to discuss his situation. Shortly thereafter, the two men left the fields by walking out the back and heading to the locker room.

It looked like Gronkowski may have pulled a hamstring, but the injury, whatever it was, clearly was not serious enough to prevent him from leaving under his own power. It was enough, however, to keep Gronkowski out of the remainder of the practice session.

Foot-brawl

What had been a relatively sedate joint practice between the Bears and Patriots escalated rather quickly toward the end of the afternoon. During the 11-on-11 team period, Bears receiver Alshon Jeffery engaged cornerback Malcolm Butler on a running play that went to the opposite side of the field. The two players were not really involved in the play at all, but Jeffery appeared to get a bit physical in blocking Butler, who took exception to the rough treatment.

Both men began shoving one another and before long resorted to grabbing one another's facemasks. It appeared as if the incident was about to die down at that point when another Chicago player, reserve tight end Greg Scruggs injected himself into the dustup by charging at Butler.

This incited a larger, more violent confrontation between a couple dozen players, although most of them seemed to be trying to break up the fracas.

Once things settled down, Butler was sent off the field by head coach Bill Belichick, who has a zero-tolerance policy for practice-field fighting.

"When you do that, you have to get kicked out, just like a game, and then go inside. That's what happened [to Butler] today," safety Duron Harmon explained. "Malcolm Butler's a talented player and we don't want that to happen. We don't want to lose him because he's a big part of what we do.

"There's really no place for it on the football field. We've got to not let our tempers rile up that much and just continue to have discipline, even when stuff's not going the way you want it to. Just continue to stay focused and remember the bigger picture."

Later, during the field goal period, tight end Martellus Bennett – an outspoken former Bear – was blocking for Stephen Gostkowski's kicks when at least two of his former Chicago teammates shoved Bennett to the ground.

Again, players grappled for a few brief moments. Bennett continued to jaw with the Bears involved, prompting Belichick to come over and get between his player and the opposing team to diffuse the situation.

[wysifield-embeddedaudio|eid="459691"|type="embeddedaudio"|view_mode="full"]"There's no ill will or anything like that," Bears head coach John Fox insisted after practice, in reference specifically to Bennett's history with Chicago. "Sometimes it doesn't work out. There's a business side, a football side, a bunch of things that happen in the course of a football career. I still wish Martellus the best."

Bears QB Jay Cutler, a high-profile target of Bennett's public criticisms, shrugged off the incidents.

"It's tough. It's a contact sport," he remarked. "They were light skirmishes. Small ones."

"It's not a good thing to fight in practice by any means," Patriots passer Jimmy Garoppolo pointed out, adding that he has mixed emotions about seeing fisticuffs on the field.

"You like to have guys on your team with that type of mindset. It's football, it's a physical game. Things are going to happen out there. You want to have a guy on your team who's going to have your back. I think our team's full of those type of guys.

"It's football. Sometimes that happens," added defensive end Chris Long, "but it's our job out here to make the most of our reps, be professional. We're going to continue to try to do that."

Brotherly love

Two players who weren't about to take swings at one another were Long and his brother, Bears offensive lineman Kyle Long. The two were all smiles as they walked off the field together and entertained media questions for a few moments.

There's a four year age difference between the two, and although Kyle is noticeably bigger than his older brother, he clearly respects Chris. In particular, Kyle noted that Chris has been supportive of him throughout his often turbulent football career.

"He's a great older brother and a heck of a football player. The Pats are lucky to have him. Big-time, he was very helpful. I could watch him do what he does. You see the way he goes about his business and the respect he's earned from guys around the league."

"Listen, he's a really good kid," Chris said of his younger brother. "I've just enjoyed watching him grow into being a man in this league. He grows up every year. It's fun to see him get better every year."

Chris is in his first year with the Patriots after eight seasons with the Rams. The past few campaigns for Chris have been marred by injuries, but Kyle said he saw a new and improved Chris on the other side of the football during practice Monday.

"He's really athletic, moves around really well. He's good with his hands. What I really like to see, with him coming off some stuff the last few years, He looks strong, feels strong. He's a competitor. It's fun to be out here with him."

Stock Watch

*Buy: *Trey Flowers – Though sometimes overmatched defending the run, the second-year defensive end has shown a consistent ability to pressure the quarterback and has seen increased reps with veterans Rob Ninkovich and Jabaal Sheard nursing injuries.

Sell: Rob Gronkowski – OK, he's still a dominant force when he wants to be, but even before his apparent injury on Monday, the All-Pro tight end has dropped at least one routine pass almost every day of camp. Very unlike him.

Play of the Day: At the tail end of the 11-on-11 team period, QB Jimmy Garoppolo took a red zone snap and zinged a pass just beneath the cross bar of the goal post. Rookie receiver Devin Lucien beat his Bears defender, jumped up to snag the bullet out of the air, and toe-tapped both feet in bounds to secure the score.