It has been said that running backs in the National Football League see a decline in production when they hit the age of 30. Barry Sanders, Adrian Peterson and Tiki Barber are just a few examples of running backs to excel at the age of 30 or older.

With that being said, running back DeMarco Murray has announced his retirement from the NFL. Murray, 30, spent seven seasons in the NFL. Most notably a member of the Dallas Cowboys and Tennessee Titans, Murray spent one season with the Philadelphia Eagles.

Murray announced his retirement Friday on NFL Live.

"I think it's time for me to hang it up, as hard as it is," Murray said. "It's bittersweet, but I think for me, it's the right timing for myself and my family moving forward."

In 99 games, Murray rushed for 7,174 yards totaling 49 touchdowns. Murray was also a threat in the passing game. He caught 307 passes for 2,165 yards and six touchdowns. He was a two-time Pro Bowler and was a First-Team All-Pro in 2014.

Career throughout the years

Murray was selected by the Dallas Cowboys in the third round of the 2011 NFL Draft from Oklahoma. He led the NFL in rushing in 2014 with 1,845 yards on 392 carries, the most attempts of any player since 2000.

He was signed a five-year, $42 million contract with the Eagles in 2015, but managed just 702 rushing yards on 193 carries (3.6 yards per carry). This would prove to be a weird time in the franchise. Then-head coach Chip Kelly did not utilize some of the best players to their full potential. He would split carries with Darren Sproles and Ryan Mathews during his lone season in Philadelphia.

Murray was traded to the Titans the following offseason and enjoyed a career resurgence in his first season in Tennessee, rushing for 1,287 yards on 293 carries. In 2017, Murray’s carries were limited due to the rise of Derrick Henry. He was released in March and did not sign with another team.