ST. LOUIS — Steven Jackson was one of the NFL's best running backs before the St. Louis Rams concentrated on offensive line upgrades in the offseason.

Now that they've added a center and selected a tackle with the second pick of the draft, he expects even more.

The Rams' desire to build around their bruising running back in a West Coast offense is reflected in the new guys who'll help open the holes, ex-Ravens center Jason Brown and ex-Baylor tackle Jason Smith. Jackson was optimistic after the Rams, 5-27 the past two seasons, opened their second minicamp on Friday.

The Rams also upgraded at fullback with Mike Karney getting a three-year free agent deal. Jackson said he and Karney have already shared several meals while getting to know each other.

"It feels really good," Jackson said. "We've made decisions in the draft and free agency to help me out. I think that's the biggest thing, you just don't want to throw it on one guy and don't give him anything to work with."

The 310-pound Smith will begin his pro career at right tackle, with Alex Barron taking Orlando Pace's old spot on the left side. Rookies are being thrown in with the veterans this weekend, so they're learning on the run.

"With the volume we're going to throw at them as we go here, if they can absorb that and spit it back out that's pretty impressive," coach Steve Spagnuolo said. "The vets are expanding a little bit on the scheme and the rookies certainly are just trying to learn the basics right now."

Jackson has topped 1,000 yards all four of his pro seasons, getting 1,042 yards in 2008 despite missing four games and most of a fifth with a quadriceps injury. He's missed eight starts the past two seasons because of injuries, leading the Rams to suggest changes in his offseason conditioning.

The 6-2, 235-pound Jackson said the biggest problem is he's too lean.

"I've just got to put on some body fat," he said. "My body fat is so low I'm susceptible to tears and cramps, and I'm trying to beef up in that area."

Jackson joked to reporters that the best way to accomplish that was to "hang out with you!"

Seriously, Jackson is looking forward to increased locker room responsibility since the Rams released veterans Torry Holt and Pace in the offseason. Only one player remains from the last Super Bowl run after the 2001 season, defensive end Leonard Little.

"I've seen the nasty side of veterans and I've seen the good side of veterans," Jackson said. "When someone is released, when someone plays for another team, I feel like I should be his friend no matter where he is in the league, that he can come to me for advice when he's going through something."

Jackson said he'll do what he can to ease the transition for the team's new running back, seventh-round pick Chris Ogbonnaya of Texas.

"You've been dreaming about this all your life and you're finally just thrust into the fire and it can be a little overwhelming," Jackson said. "Any time they mess up, I try to pull them to the side and get those guys to calm down.

"That's the biggest thing: You're so nervous, you want to do everything right, and that's when everything goes wrong."

Notes: Spagnuolo said WR Derek Stanley, recovering from knee surgery, may not be cleared for full duty before training camp. ... Oklahoma WR Quentin Chaney, one of 15 undrafted college players signed on Monday, failed a physical.