There was a time when Trent Richardson was considered one of the top up-and-coming running backs in the NFL. It was a long time ago.

Now, Richardson is starring in the Alliance of American Football, a new league that just opened this month.

Richardson, who plays for the Birmingham Iron, rushed for 56 yards and a couple of touchdowns in a 26-0 win over the Memphis Express, who featured former New York Jet Christian Hackenberg at quarterback.

Oh, and remember Zach Mettenberger of the Tennessee Titans? He is Hackenberg's backup.

Trent Richardson, who played his collegiate football at the University of Alabama, was originally selected by the Cleveland Browns with the third overall pick of the 2012 NFL Draft.

He played in 15 games during his rookie campaign, rushing for 950 yards and 11 touchdowns. However, he averaged just 3.6 yards per carry. In addition, Richardson hauled in 51 receptions for 367 yards and a score.

The following year, the 28-year-old played in just two games with the Browns before being traded to the Indianapolis Colts for a first-round draft pick. In 16 contests overall in 2013, Richardson finished with just 563 yards and three touchdowns, averaging a meager three yards per attempt.

He spent one more season with the Colts in 2014, accumulating 519 yards while reaching the end zone three times on the ground, registering 3.3 yards per carry.

Trent Richardson was then waived by Indianapolis that offseason and signed with the Oakland Raiders. However, the Raiders let him go before the 2015 season started. He then signed with the Baltimore Ravens, but never actually played a game for them.