Oklahoma coach Bob Stoops started the spring with some praise for his team. Then he paused.

The offensive line that protected Sam Bradford as he threw for 50 touchdowns in 14 games mostly departed after the BCS national championship. What was coming up had been less than impressive in the two months since.

“Those guys are at this point, it’s just everything, whether it’s with their work ethic, their attitude, those things need to improve,” Stoops said at a press conference Tuesday afternoon that coincided with the start of spring practice. “They haven’t had the winter everyone else has had. They right now are the weak link of the team and we’ll see if they can respond and have any kind of spring and summer to help us be a team that can contend for a Big 12 Championship.”

Stoops usually saves harsh critiques of his players for closed-door situations. There have been only rare instances in his 10 seasons where he’s called out individual players, much less an entire unit.

It didn’t come as a surprise, though.

“I’ve received a lot conversations about that,” guard Brian Simmons said following Tuesday’s practice. “We have a lot of shoes to fill and I understand a lot is expected of us.”

Tuesday was the first of 14 practices and scrimmages the Sooners will conduct prior to the Red/White game April 11. It is in that period they will go about replenishing an offensive line that is going through changes.

All-American guard Duke Robinson, all-Big 12 tackle Phil Loadholt, all-conference center Jon Cooper and guard Brandon Walker are gone from last season’s starting five. Top reserve tackle Branndon Braxton also played his final game against Florida.

All that’s left from the group that opened holes and protected Bradford the last two seasons is tackle Trent Williams and Simmons, who started two games and played in the rest last season.

Stoops’ irritation stemmed from reports he received from strength coach Jerry Schmidt about the workouts over the last two months.

“Just coming to work every day, having a tough attitude, having some discipline to do the things you’re supposed to do on the field and off. To this point, they haven’t done that,” Stoops said.

The message has been received. What changes remains a work in progress.

Williams is the one the Sooners will try to rebuild around as he makes the switch to left tackle for next season. He’s started at right tackle the previous two years. Simmons is next to him at left guard. Center Ben Habern, right guard Stephen Good and right tackle Cory Brandon have at least made it to the depth chart at the start of spring drills.

Nothing is set in stone, though. Getting called out by the head coach before spring practice even started made that obvious.

Even without the wealth of experienced offensive linemen OU enjoyed the last two seasons, the standard won’t change.