Lamar Miller won the running back competition with Daniel Thomas and will start the season opener, according to the team's Week 1 depth chart.
A fourth-round pick in 2012, Miller entered the preseason battling with Thomas to replace the Reggie Bush in the backfield and said getting the start Sunday against the Browns would be a "dream come true."
Miller rushed for 250 yards and a touchdown in 52 carries as a rookie, and averaged 4.2 yards per carry this preseason.
Thomas, who struggled this preseason, was listed as Miller's backup on the season-opening depth chart. Thomas will play a role in the offense, as coach Joe Philbin has maintained throughout the competition.
Durability could be the buzzword for the tandem. Thomas, who had 91 carries last season, and Bush battled injuries and the Dolphins haven't had a primary back exceed 250 carries since 2003, when Ricky Williams had 392 rushing attempts. To reach 300 carries, a running back would need to average 19 per game.
Miller said in training camp his goal is 1,500 yards, isn't considered a polished pass blocker but not necessarily because of his physical stature.
"Lamar is a very smooth back and he's more powerful than you'd think," offensive coordinator Mike Sherman said.