Coach Pete Carroll said Thursday that the Seattle Seahawks expect to be without defensive end L.J. Collier for a matter of weeks after the first-round pick suffered an "unusual" and "badly sprained ankle" on Tuesday.

Collier went down in obvious pain during Tuesday's practice while rushing on a passing play.

Speaking with reporters for the first time since Collier was hurt, Carroll said Thursday "it's going to be a little bit" before Collier returns. The coach didn't specify any timetable beyond that, but the impression he left was that Collier could be out for the preseason if not beyond.

"It's unfortunate," Carroll said. "Really an awkward position he got tangled up in. So we'll have to take some time here to figure it out. It's going to be some weeks, though.

"It's not a garden-variety sprain at all. It's a little but unusual one. Kind of the upper part of his foot. An unusual one for us. We really haven't had a guy that sprained his ankle just like this, so that's why we're really going slow to make sure we know what we're doing with this. It's a rare sprain."

Collier was taken inside on an injury cart Tuesday after walking off the practice field with a pronounced limp. He hadn't seen much time with the No. 1 unit during training camp, but the Seahawks were counting on him to provide some immediate help to a defensive line that lost Frank Clark via trade and will be without Jarran Reed for the first six games of the season due to a suspension.

Ezekiel Ansah, signed in May to help replace Clark, began training camp on the active roster as opposed to the physically unable to perform list but has yet to begin practicing. The team believes he'll be ready by around the start of the regular season.

The Seahawks envision Collier as a five-technique defensive end on early downs and an inside rusher in passing situations. Asked if they will need to sign someone on account of Collier's injury, Carroll said they'll continue to look, as they always do. The Seahawks had interest in former Green Bay Packers outside linebacker Nick Perry earlier in the offseason. He remains unsigned.

"That hits our depth though a little bit, but we do have guys to fill in playing the five-technique spot," Carroll said. "Quinton Jefferson is doing a nice job and also Rasheem Green can go over there, too. So I don't think we're out of it now numbers-wise. We're OK, but we've got to be careful."

Jefferson made 12 starts last season. Green, a 2018 third-round pick, played sparingly as a rookie. Seattle's other edge players include Cassius Marsh, Barkevious Mingo, Jacob Martin and Nazair Jones.

Mike Iupati, the presumptive starter at left guard, has been out the past two practices with what Carroll called a mild foot sprain. The coach noted that Iupati is already out of his walking boot and shouldn't be sidelined for much longer.

Undrafted rookie tight end Justin Johnson went down Thursday with what the team fears is a torn Achilles tendon, Carroll said.