DAVIE, Fla. (AP) Mediocrity, the Miami Dolphins' hallmark in recent years, suddenly seems beyond their reach.

The Dolphins are staggering to the finish line with another dismal December and are now assured of their first losing season since 2012. They're 5-9 with games remaining at home against two teams thinking playoffs, Indianapolis and New England.

Lose both, and the Dolphins will have their worst record since 2007, when they went 1-15. Regardless, this year is a step back from the past two seasons, when Miami went 8-8.

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Movement in the wrong direction gained momentum with Sunday's 30-14 loss to the last-place San Diego Chargers. The Dolphins entered the game already eliminated from the playoff race and played like it, trailing 23-0 at halftime.

''I don't fault the effort,'' interim coach Dan Campbell said Monday. ''They fought all the way through. Mentally the focus was not there. That's what lacked.''

Focus isn't the only issue. Center Mike Pouncey (left foot), linebacker Koa Misi (back) and linebacker Chris McCain (knee) left Sunday's game with injuries that could be season-ending, and left tackle Branden Albert (right knee) also went to the sideline.

With Pouncey and Albert out, the offensive line found it difficult to protect Ryan Tannehill, who was sacked three times and had his right hand bandaged afterward.

Third-year pro Dallas Thomas might be the most experienced blocker in a patchwork line against the Colts.

''Hey, it'll be interesting,'' Campbell said. ''If that's who we've got, that's who we've got, and we'll make a go of it.''

Tannehill has taken a beating this season, but if he's eager for it to be over, he isn't saying. Instead, he sees the remaining games as a chance to create momentum toward 2016.

''I'm still out there to play to win,'' Tannehill said. ''You only get 16 regular-season games a year, and you want to take advantage of every single one. You want to build off the things we've done well, and correct the things we haven't done well. We know it's our last two games, but I think we need to find a way to play well and build off of that for next year.''

Eight rookies saw significant duty against the Chargers. When Campbell was asked about any bright spots in the loss, the first player he mentioned was fifth-round pick Tony Lippett, who saw extensive action at cornerback.

Campbell also praised first-round pick DeVante Parker, who had four receptions for a season-high 87 yards.

''He's taking his game to another level,'' Campbell said. ''He's beginning to play with a lot of confidence, and you can tell the defenders over him are feeling that. As the game went on, they started playing a little more off him.''

The rookie players will be back next season, but the rookie coach probably won't. Campbell's promotion when Joe Philbin was fired inspired Miami's best stretch of the year, with consecutive lopsided victories before the team went into a tailspin.

The Dolphins are 4-7 since Campbell took over and have lost five of the past six games. Even so, their interim coach continues to win praise from his players.

''At this point playoffs are obviously out of the question,'' running back Jay Ajayi said, ''so we're all playing for love of the game and our teammates. I'm going to put my heart on my sleeve for coach Campbell, because he has been great through this whole situation.''

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