Baltimore Ravens head coach John Harbaugh has admitted that his team's running game needs a complete overhaul after a nightmare 2013.

Running backs Ray Rice and Bernard Pierce had extremely disappointing seasons, with fewer than 1,100 rushing yards between them and just six touchdowns to their names.

Their poor campaign came after a Super Bowl-winning year, however Harbaugh has said that one tough season is enough for him to decide changes need to be made.

Harbaugh told The Baltimore Sun: "I think the whole thing just needs an overhaul. It was many things. We didn't block people well. We didn't move people. We didn't get on people.

"Our backs both weren't 100% and they didn't make enough guys miss, and didn't break enough tackles."

Rice is facing possible discipline from the NFL for his recent arrest while Pierce is recovering from shoulder surgery.