He picked up the injury in the third quarter of Friday night's preseason game against the Redskins, which the Jets lost 16-11.
Pace appeared to walk very gingerly in the locker room and was wearing a large protective boot on the foot. He declined comment, saying he would speak early in the week.
"We expect him to be out a few weeks," said Jets coach Rex Ryan, who wasn't sure if there was a fracture or not.
"It's a big loss, but we're fortunate we have a lot of depth at that position. Jason Taylor's role is going to change from 75 percent [of the snaps] to 100 percent until Calvin comes back."
Pace, who missed the first four games of last season because of a substance-abuse suspension, led the team with eight sacks in 2009 and is their best pass rusher.
Now the focus will be on Taylor, who was brought here to be a part-time pass rusher. Taylor insisted he was ready for a bigger role.
"I wasn't going around telling everybody I was a situation guy," Taylor said. "I want to play."