DAVIE, Fla. -

South Florida has not been kind to new Dolphins running back Knowshon Moreno.

Signed to add firepower to Miami's lagging rushing attack, Moreno is reportedly suffering from a knee injury that may require surgery.

Profootballtalk.com is reporting that Moreno has been dealing with a left knee issue that has limited his time during the team's workouts this week.

Moreno, who signed a one-year, $3 million deal during the offseason, tore the ACL in his right knee in 2011.

The report goes on to say that Moreno may need arthroscopic surgery, but that the 6-year NFL veteran would likely be ready for the start of training camp.