Both teams are in last place and eliminated from the playoff race, but the stakes are sizeable for Lippett, who might get his first NFL start. The Dolphins' rookie cornerback and fifth-round draft pick is especially raw because he played mostly receiver at Michigan State, but coaches like his potential and plan to give him an extensive audition against the Chargers.
''This week feels a little different,'' Lippett said Wednesday. ''I've probably got a little more focus and attention to detail, and I'm watching a little more film. But I don't want to let the moment get so big I can't compete.''
While Lippett will likely have butterflies come kickoff, others might struggle to stifle a yawn. The Dolphins (5-8) are out of the playoff race for the seventh year in a row, a franchise record, and this is the earliest they've been eliminated since 2011 - three head coaches ago.
The situation is even more distressing in San Diego, where the Chargers (3-10) might play their final home game before a possible move to the Los Angeles area.
For both franchises, lots of change is coming. Dolphins interim coach Dan Campbell is 4-5 since taking over, and Miami might soon begin searching for its ninth coach since 2004.
Plenty of players will soon be moving on - but that doesn't necessarily undercut motivation Sunday, Miami center Mike Pouncey said.
''You're not just playing for the Dolphins,'' Pouncey said. ''You're playing for 31 other teams. What you put on film is who you are. If you go out there and give up on the season and don't play hard these last three games, that's who you are.''
Two players joined the roster this week just in time to miss the playoff race.
Defensive end Damontre Moore joined the Dolphins on Wednesday after being waived last week by the New York Giants. Moore, a former third-round pick, tried to shrug off his reputation for clashing with Giants coach Tom Coughlin and management.
''I was very immature during my time up there, but I learned from my mistakes,'' Moore said. ''I'm in South Beach, baby. Why are we still talking about New York?''
Tannehill was also ready to look ahead, but acknowledged he was still stewing about Monday's 31-24 loss to the Giants. He led the Dolphins to only one second-half score, and overthrew an open Jarvis Landry behind the secondary with five minutes left.
''I feel like I played a good game, but I missed that last throw,'' Tannehill said. ''It's one that I've thought a lot about since then. It has kind of haunted me a little bit. But there's nothing I can do about it now - just make the throw next time it pops up.''
Notes: LB Jelani Jenkins (ankle), CB Bobby McCain (concussion) and DT Earl Mitchell (calf) didn't practice Wednesday. T Ja'Wuan James (left toe) and WR Rishard Matthews (ribs) returned but were limited, while Landry (knee) and RB Lamar Miller (ankle) were limited. .. To make room on the roster for Thomas, the team waived guard-tackle Jeff Linkenbach.
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