BEREA, Ohio (AP) — Cleveland Browns Pro Bowl running back Nick Chubb has been placed in concussion protocol after he sustained a head injury while being tackled during the team’s first fully padded practice.

Chubb, who finished second in the NFL last season with 1,494 yards, was taken down during Monday’s workout with a high tackle by second-year linebacker Mack Wilson.

The third-year back will sit out Tuesday’s workout and per league rules Chubb will have to pass several neurological tests before he’ll be permitted to return to the field.

Coach Kevin Stefanski didn’t specifically comment on Wilson’s tackle but he said it was fair to say he wasn’t happy with losing one of his best players to an aggressive play.

“Yeah, that was disappointing,” he said. “We’ve got to be smart. We’ve got a lot of work to do and we’re going to continue to have our pads on and we’ve got to make sure as a team that we get our work done and get it done while taking care of each other.”

Chubb caught a short pass and was trying to get to the corner on the left side when he was grabbed around the head and neck area by Wilson. A few minutes later, Chubb walked to the team’s facility escorted by a member of the team’s medical training staff.

Chubb hasn’t missed a game since being drafted in the second round in 2018. He was in line to win the league rushing title last year before he was surpassed by Tennessee’s Derrick Henry in the final week.

While he’s sidelined, Kareem Hunt will be Cleveland’s primary ball carrier. He’s in his second season with the Browns, who signed him as a free agent last year after he was released by Kansas City following a violent off-the-field incident that resulted in an eight-game league suspension.

Hunt was the league’s leading rusher as a rookie with the Chiefs in 2017.