AP Sports Writer
ST. LOUIS (AP) -- Zac Stacy made his mark as a fifth-round pick last year, falling just shy of 1,000 yards. Now, the running back must prove his worth all over again.
The St. Louis Rams sent a message in this year's draft, taking Heisman Trophy finalist Tre Mason in the third round. And though they've released Daryl Richardson, undrafted rookie Benny Cunningham was impressive last season and former second-rounder Isaiah Pead remains in the mix.
There's always going to be someone gunning for the job.
"Oh absolutely, there's going to be competition," Stacy said. "There's no doubt about that."
Stacy has the advantage heading into training camp because he knows the routine, has a better grasp of the playbook and knows firsthand about the pounding that must be absorbed.
"You know what to expect, you know what's going on," Stacy said. "Last year, as rookies we were all running around like chickens with our heads cut off. It's been great so far."
Mason was the SEC offensive player of the year and the first non-quarterback to lead Auburn in total offense since Bo Jackson in 1985, running for 1,816 yards with 23 touchdowns and setting school single-season records for all-purpose yards and rushing TDs.
Given Mason shredded Missouri for 304 yards and four TDs in the SEC championship game, he arrived at Rams Park a well-known commodity. He won't be satisfied as a change-of-pace option, coach Jeff Fisher's initial assessment.
"Not sure how it starts out, and you never know what can happen in the future," Mason said. "I'm here to do what they ask of me."
Stacy's rookie season is a good example. The first four games, he was inactive twice and totaled 4 yards on a single carry.
Stacy is Vanderbilt's career leading rusher. Mason was a much bigger star in the SEC for Auburn's national championship runners-up and deemed a premium pick.
"I'm happy for Tre or whatnot," Stacy said. "Obviously, with him being one of the top college running backs last year, we know the things he can do, and it's all about the adjustment to the playbook."
Stacy aims to make everything come naturally on the field, so he's not taking the team's OTA sessions lightly
"Very important, very important," Stacy said. "Treating every rep like it's a game rep."
Richardson was the starter entering training camp last summer, coming off an effective rookie season as the Steven Jackson's understudy, but was dogged by foot injuries. Stacy got the starting job in Week 5 and didn't let go.
He's not wasting time fretting about settling for 973 yards when the 49ers held him to 15 yards on 15 carries in the finale.
"My mentality is to go out and be productive," he said. "Being consistent with my play, I think the yards and stats and accolades will come."
Stacy is a compact 5-foot-9 and 224 pounds, runs low to the ground, hits the hole quickly and can bounce off tacklers. The Rams rested him most or all of practice weeks, allowing him to recover from the punishment and stay fresh for game days.
Mason is an inch shorter and 20 pounds lighter but was extremely durable at Auburn, and big in the big games. He followed up his signature game against Missouri with 195 yards rushing in the national championship game against Florida State.
He's still running behind college teammate and close friend Greg Robinson, the second overall pick of the draft, who'll begin his career at left guard.
"I've got to do it to learn it," Mason said. "I'm the type of guy who's hands-on."
Cunningham, 5-foot-10 and 217 pounds, was undrafted out of Middle Tennessee. Both he and Stacy had 100-yard games against the Bears in Week 12, and he totaled 261 yards in limited duty with a 5.6-yard average.
Pead had 21 yards on seven carries, all in the first two games of the season, plus 11 receptions with a 7.1-yard average. He reportedly was shopped during the draft.
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