FOXBOROUGH, MASS. >> Tight end Rob Gronkowski left the first day of joint practices between the Patriots and Bears on Monday with an apparent lower-body issue.
Gronkowski made awkward cut while running a route during 7-on-7 drills. He grimaced after the play and paused briefly before jogging back gingerly to rejoin his teammates.
He was then led back to the locker room by a trainer and did not return.
"Hopefully he's all right, and we'll see what it is," quarterback Jimmy Garoppolo said.
Monday was the first of three joint practices the teams will have in advance of Thursday's preseason matchup.
New England's gregarious big man and a fixture in New England's offense, Gronkowski was absent from the practice field during the majority of organized team activities in June. He didn't play in last week's preseason opener against New Orleans.
A prolonged absence for him would be another setback to a Patriots team that will be without starting quarterback Tom Brady for the first four regular-season games while he serves his "Deflategate" punishment.
Later in the day tempers flared between Patriots cornerback Malcolm Butler and Bears receiver Alshon Jeffery, leading to an extended shoving match.
It intensified into about a 30-second scrum after teammates intervened.
Both Butler and Jeffery were ejected from practice as part of an earlier agreement between New England coach Bill Belichick and Chicago coach John Fox.
Bears quarterback Jay Cutler said the incident involving Jeffery was indicative of his intense nature.
"He enjoys stuff like this," Cutler said. "He's a competitor. He likes games. He likes big moments. He wants the ball in those types of situations. He's not gonna back down from guys. He's gonna go up and make the catch. If you get in his face, he's not gonna take it lightly."
A shorter incident occurred toward the end of the workout between Patriots lineman Nate Solder and Chicago linebacker Lamarr Houston.
But Fox said he isn't worried about the issues spilling over into other practices.
"At some point you kind of have to manage your emotions and the closer you get to real games, the more important that is," he said. "It's kind of part to the process and you just try to make sure it doesn't happen in games."
The Patriots did get some welcome news on the injury front as receiver Malcolm Mitchell returned to practice after sustaining a left elbow injury in the second quarter of New England's preseason win over the Saints.
Mitchell was in full pads and wore a brace on the elbow Monday. But he didn't participate in any live drills, and instead did some light conditioning on a secondary field alongside other inactive Patriots, including Danny Amendola and Rob Ninkovich.
Notes: Fox said TE Zach Miller, who is back on the practice field after sustaining a concussion July 31 is working his way through the concussion protocol. "Part of the protocol is they can come out here and run around, and part of clearing that is how you feel after exercise," Fox said.