Trent Richardson

Some have called Trent Richardson one of the biggest busts of all time.

Among NFL running backs with at least 500 carries, the No. 3 overall pick in the 2012 draft owns the second worst yards-per-attempt average since the NFL-AFL merger. Only former Eagles/Packers running back Michael Haddix's 3.01 yards was worse than Richardson's 3.33.

Two different NFL teams traded first-round selections for Richardson, who seemed like a sure-fire candidate to succeed in the NFL.

"Everybody felt like, 'OK, he might not be the third pick in the draft,'" said Phil Savage, the Crimson Tide's radio analyst since 2009 and the Browns general manager from 2005 to 2008. "But he was a first-round talent."

Trent Richardson

During Richardson's three years at Alabama, he displayed that talent, performing at the highest level (3,860 yards and 42 touchdowns) while facing elite competition (the SEC) at a position that typically translates well from college to the pros (running back).

But now the 25-year-old, who was released by the Raiders before the 2015 season, is out of the league.

How has the highest running back selected since 2006 fallen to such depths?

His descent may have started with his last collegiate contest. During the BCS national championship game against LSU in 2012, Richardson tore meniscus in his left knee and had surgery Feb. 3, 2012. Richardson then had another arthroscopic surgery on the same knee the ensuing August but returned to play in Week 1.

Before the injury, he had NFL-caliber speed, consistently running the 40 in under 4.5 seconds. The balky knee not only slowed him, but also likely played a role in causing his weight to balloon, making him less nimble.

"I'm not sure he ever got in top-notch condition," said Savage, who also serves as executive director of the Senior Bowl.

Richardson was a great scheme runner. Tell him to hit the gap between the right tackle and tight end, and he'd burst through it, executing it perfectly. But the NFL employs a lot of zone blocking, asking the runner to go where their eyes take them.

Trent Richardson

"His vision has probably been an issue for him," Savage said. "He was not a particularly great zone runner."

In addition to his on-the-field issues, he struggled adjusting to the NFL life. At Alabama he was insulated by the structure of a typical big-time program, instructing him where to go and what to do as part of its rigid schedule.

Once he left Tuscaloosa, he was no longer nestled by that support system. One source suggested that the four-year, $20.5 million rookie contract he received from the Browns actually created problems for Richardson, who grew up poor in Pensacola, Florida, and had hanger-ons looking for money.

"He's not handled his affairs off the field," Savage said.

The final straw came when Richardson -- whose girlfriend went into premature labor, according to The Indianapolis Star -- didn't tell the Colts he would miss the walk-through practice the day before last season's AFC championship game.

***

During Mark Ingram’s Heisman Trophy-winning, national championship 2009 season at Alabama, there was a tacit belief among Crimson Tide insiders regarding his fledgling backup.

"There was a feeling within the program that," Savage said, "this true freshman's going to be even better."

After running for 1,451 yards and 14 touchdowns for Alabama from 2009 through 2010 behind Ingram, Richardson ran for 1,679 yards -- while averaging 5.9 a rush -- and 21 touchdowns when he became the starter as a junior in 2011.

Trent Richardson

Very powerfully built, the physical 5-9, 228-pounder ran hard and was a savvy pass protector with good hands. At his 2012 pro day, Richardson ran the 40-yard dash in the 4.45 to 4.49 range and bench-pressed 225 pounds 25 times.

"He worked hard in the weight room. He practiced hard," said Jets guard James Carpenter, who started every game at left tackle for the Crimson Tide in 2009 and 2010. "He was like the toughest dude I ever met."

Those close to Richardson lauded his competitiveness and heart, which makes his failures in the NFL all the more surprising. After scoring a rushing touchdown in college, he often sprinted down on the subsequent kickoff team to tackle the returner.

The Browns were so enamored with Richardson's positives that they traded their fourth overall pick, a 2012 fourth-round pick (118th overall), a 2012 fifth-round pick (139th overall) and a 2012 seventh-round pick (211th overall) to the Vikings to move up one spot, where they selected Richardson at No. 3. (Quarterbacks Andrew Luck and Robert Griffin III were the first two picks. The next running back selected was Boise State's Doug Martin at 31st overall by the Buccaneers.)

But after he struggled with the Browns, Cleveland traded Richardson just two weeks into his second season to Indianapolis, who gave up its 2014 first-round pick for him.

Richardson lasted less than two seasons with the Colts.

***

Richardson, who played at Alabama from 2009 to 2011, is part of a succession of great Crimson Tide running backs.

Trent Richardson

From 2008 to 2010, Ingram rushed for 3,261 yards and 42 touchdowns, including 1,658 during his Heisman season. Richardson was his backup until becoming the starter in 2011.

Hindered by various injuries, Ingram has shown flashes during his five years in the NFL but hasn't lived up to where he was drafted in the first round (28th overall) in 2011. He's coming off his best year, a Pro Bowl season in 2014 when he rushed for 964 yards and nine touchdowns while averaging 4.3 yards per carry.

Richardson's backup was Eddie Lacy, who rushed for 2,402 and 30 touchdowns from 2010 to 2012. Lacy has surpassed 1,100 yards in both of his NFL seasons and has been the most successful of this lineage of Alabama runners. Of course, he also came into an ideal situation in Green Bay, where he complements Aaron Rodgers' terrific passing game.

Lacy’s Alabama understudy was T.J. Yeldon, who rushed for 3,322 yards and 37 touchdowns from 2012 to 2014. Like Lacy, Yeldon was drafted in the second round and has held an NFL starting job from Day One.

Derrick Henry, a junior, is the next in line. He backed up Yeldon, the current Jaguars running back, the past two years before taking the reins this season.

Trent Richardson

Henry, who had 990 yards and 11 touchdowns for the Crimson Tide in 2014, gained fame after breaking the all-time high school rushing record. He likely will be selected early in the 2016 NFL Draft.

Whether Richardson can rejoin his Alabama brethren in the NFL remains very much in doubt.

Before the 2015 regular season, the Raiders released him after he gained just 42 yards on 15 carries during three preseason games. That may have been his last chance in the NFL.

"It's going to be a real uphill battle for him because he's already been with three teams," Savage said. "The old adage: Three strikes and you're out."

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-- Follow Jeff Fedotin on Twitter @JFedotin.