LSU running back Darrel Williams (28) carries the ball against Louisville in the third quarter of the Buffalo Wild Wings Citrus Bowl, Saturday, December 31, 2016, at Camping World Stadium in Orlando, Fl.

Teammates developed a nickname for LSU running back Darrel Williams.

They call him — or, at least, they called him — “Fat Darrel.” The rising senior shrugged this off.

The problems arose when his mother — his mother! — began calling him by a similar name.

“What really motivated me is my momma started calling me fat,” Williams said. “My momma never called me fat. For her to call me fat, I realized I really am fat.”

Not any longer. Williams lost about 15 pounds since the football season ended, dropping to a weight of 225.

He’s lighter, feels faster and he's receiving the bulk of carries during spring drills, a testament to his weight loss, his classification (he’s the senior leader in the running back room) and the absence of starter Derrius Guice (minor ankle sprain).

Williams led the team with 20 carries and 93 yards in last week’s scrimmage. He’s never had this many carries in practice since his high school days, and he's feeling it, too, spending afternoons in the cold tubs full of ice.

Halfway through spring drills, Orgeron and players have included Williams as one of the most improved players during spring, along with guys like receiver Drake Davis, cornerback Kevin Toliver, center Lloyd Cushenberry and guard Garrett Brumfield.

It’s got plenty to do with that weight loss, which had plenty to do with ending his fast food cravings. Williams went from eating Raising Cane’s and Taco Bell to baked fish and baked chicken.

“It’s hard, but I got to get it done,” he said. “I just wanted to be back to my old self. I never weighed that much. I just wanted to get back down to the old Darrel.”

Former LSU running backs coach Jabbar Juluke also threatened him, somewhat playfully maybe — or maybe not.

“At the end of last season, talking to Coach Juluke, if I don’t lose weight, I won’t play in the spring,” he said. “I didn’t want to miss out on spring.”

The weight loss has resulted in more than just those extra carries. Expectations are heightened for a John Ehret graduate who averaged just 4.9 carries a game in his first three seasons here. He’s embracing his new role as leader of the running backs room and a guy coaches are counting on to be an immediate backup to a Heisman Trophy hopeful.

He’s heard that before. Williams was expected to be the immediate backup to Leonard Fournette in 2015.

“I thought my sophomore year we were going to have a good year together that year, but things didn’t work out as planned,” said Williams, who had 60 carries to Fournette’s 300 and who was, by mid-season, surpassed in the rotation by Guice.

“This is my senior year," Williams added. "I’ve got to go all out.”

Follow Ross Dellenger on Twitter, @RossDellenger.