Knowshon Moreno made his training camp debut in a white No. 28 jersey and with no visible brace on his knee at the Miami Dolphins facility Wednesday.
Moreno, who signed a one-year, $3 million deal with the Dolphins, had arthroscopic knee surgery in June.
With running back Lamar Miller having a strong camp, Moreno has some ground to make up.
Miller has been more decisive and aggressive, and brings the big-play element head coach Joe Philbin wants in his primary ballcarrier.
Moreno is more proven, and had a Pro Bowl season with the AFC champion Denver Broncos last season.
Moreno will not likely play Friday against the Atlanta Falcons in Miami's preseason opener, but is expected to work into a niche as a third-down back to open the regular season.