JACKSONVILLE, Fla. (AP) -- Jaguars receiver Marqise Lee was carted off the field Sunday with a right leg injury, a potentially significant setback for a team already without rookie running back Leonard Fournette.

Lee fell to the ground during 7-on-7 drills and immediately grabbed his leg. Linebacker Telvin Smith called for trainers.

Lee's lower leg was immobilized before he was taken off the field on a cart.

Coach Doug Marrone had no update after practice, saying "we're really not going to get anything until the doctor sees him."

The injury happened during Jacksonville's first practice in its new indoor facility. It also came hours after the team shut down Fournette.

The fourth overall pick in the NFL draft has a foot injury that Marrone is calling a "nagging issue."

"We're just being real cautious with it," Marrone said.

Fournette sat out practice Sunday and is unlikely to work against Tampa Bay in joint practices Monday and Tuesday.

"I think it's been something that has been kind of growing," Marrone said. "I think it's just one of those nagging things. It was a nagging issue.

"And then the other day it was just sore, so we were like, `Let's not take any chances. Let's take cautionary measure so it doesn't turn out to be something that could be worse.'"

Fournette ran nine times for 31 yards and a touchdown at New England on Thursday. The former LSU star is being counted on to revamp Jacksonville's rushing attack and take some pressure off quarterback Blake Bortles, who averaged 39 passes a game in 2016.

Lee, a fourth-year pro from USC, has 115 receptions for 1,464 yards and five touchdowns. He's the expected starter opposite Allen Robinson.