DAVIE, Fla. (AP) -Chad Pennington may not be available to give his winless team a much-needed lift.

The Miami Dolphins quarterback dislocated his right shoulder and may seek a second opinion to determine how long he'll be sidelined, a person familiar with his status said Monday.

The person insisted on anonymity because the Dolphins have said little about the injury. Teammates braced for a new quarterback, with backup Chad Henne expected to make his first NFL start in Sunday's home game against Buffalo.

Other media outlets reported Pennington had a torn capsule and was likely to miss the rest of the season.

``We don't have a comment, because the evaluation process is still ongoing,'' team spokesman Harvey Greene said.

Pennington hurt his shoulder Sunday in a 23-13 loss at San Diego, and he underwent tests Monday to determine the extent of the damage. An operation on the shoulder would be Pennington's third since 2005.

The quarterback shakeup comes with the Dolphins already reeling. They're 0-3 after Pennington led an improbable run to the AFC East title last season.

Henne, a second-round draft choice in 2008, has been considered Pennington's heir apparent for more than a year.

``We're going to have to go out there with Henne, who is a lot less experienced,'' tight end Anthony Fasano said. ``There is definitely going to be a learning curve for Henne. He can learn as much as he wants in a classroom, but until he's out on the field, in-game experience he's not going to learn.

``But we have a lot of faith in Chad. He's a smart guy, a great leader and fun to play with. We're just going to have to move on.''

Pennington had surgery on the same shoulder to repair a torn rotator cuff twice in 2005. Coach Tony Sparano said he didn't know how long Pennington would be sidelined.

``I can't rule anything out,'' Sparano said. ``I really don't know the details. ... We're trying to gather a little bit more information.''

The most accurate passer in NFL history, Pennington is in the final year of a two-year contract, and a serious injury could leave his career in jeopardy at age 33.

The score was 3-all when Pennington was hurt early in the third quarter. He missed the rest of the game, and Henne went 10 for 19 for 92 yards. He led the Dolphins to 10 points but threw an interception that was returned for a touchdown.

The challenge for the offense will be to develop a chemistry with Henne, receiver Greg Camarillo said.

``Chad (Pennington) is our leader,'' Camarillo said. ``Any injury to him is an injury to our offense. But it's also an opportunity for Henne to step up. We've got faith in his quarterbacking abilities. It's time for him to show it off.''

Pennington was hurt on a hit by linebacker Kevin Burnett as he threw a pass. The injury appeared to occur with the contact, which caught Pennington in an awkward position, rather than when he hit the ground, Sparano said.

``Kind of a weird-looking deal,'' Sparano said.

Linebacker Joey Porter, nursing a sore right hamstring, also was unable to finish the game because the muscle tightened. Sparano said Porter will be evaluated this week.

The injuries are another blow for a team rapidly regressing after a great leap forward in 2008, when Pennington helped the Dolphins improve their victory total by 10 games and win the AFC East. Now playoff hopes are fading fast - only three teams since 1990 have gone to the postseason after losing its first three games.

Sparano said lineup changes are possible.

``I told this team yesterday, it's not OK to be 0-3,'' he said. ``It's not acceptable. If there's a place where we can shake some things up, we will.''

The biggest lineup change may be at quarterback, but not because of a demotion.

Pennington was chosen NFL Comeback Player of the Year in 2008 and tied for second behind Peyton Manning in the vote for MVP. But he has never put together consecutive productive seasons, in large part because of injuries.

``Staying healthy is my No. 1 goal,'' Pennington said before the season.

He has missed time during his 10 years in the NFL with career-threatening shoulder injuries in 2004 and 2005, as well as a wrist injury that sidelined him for six games in 2003.

Henne would be the 14th starting quarterback for Miami since Dan Marino retired following the 1999 season. In the most extensive action of his brief career Sunday, Henne struggled with his accuracy and made a poor decision on the interception but showed good composure, Sparano said.

``I don't think at any point during the game he was flustered,'' Sparano said. ``His look and demeanor for going into the game at that point were very good, and his handle of the offense was pretty good.''

Dolphins tackle Jake Long, who played with Henne at Michigan, said everyone on the offense has confidence in the young quarterback.

``He's poised. He's a leader,'' Long said. ``When he gets his chance, he's going to do good.''Copyright © 2005 The Associated Press. All rights reserved. The information contained in the AP News report may not be published, broadcast, rewritten or redistributed without the prior written authority of The Associated Press.