Louis Riddick explains how the Rams' decision not to take care of DT Aaron Donald reflects poorly on the team (1:33)

THOUSAND OAKS, Calif. -- Les Snead, the Los Angeles Rams' sixth-year general manager, said it would "probably be a safe assumption" that Aaron Donald would not be available for the season opener if he does not report to the team by the end of this week.

The Rams still don't know if he will.

Snead spoke to reporters late Tuesday afternoon, 12 days before the Sept. 10 opener against the Indianapolis Colts, but would not divulge details about the prolonged, ongoing negotiations with Donald's representatives at CAA.

"We'll continue keeping the details in-house," Snead said. "That's for all parties."

The Rams' Aaron Donald is owed less than $9 million in base salary from 2017 to 2018, far less than other top defensive tackles in the league will make. Jeff Curry/USA TODAY Sports

But the Rams are really fighting the clock, with the start of their season now less than two weeks away. Donald was seen Tuesday by ESPN's Jeremy Fowler at his alma mater, Pittsburgh, where he has spent his entire summer training. But working out on one's own does not compare to competing against teammates in a padded practice, let alone appearing in a preseason game.

Even Rams running back Todd Gurley, who believes the preseason schedule should be trimmed to at most two games, will admit that Donald faces obstacles with that first practice.

"He's gonna be hurting," Gurley said, laughing. "It don't matter. I work out three times a day during the offseason. You come back, that first day of practice, it is what it is. That's just football for you. It takes some time. I'm pretty sure he's grinding, but it's definitely different."

Pittsburgh Steelers running back Le'Veon Bell recently tweeted that he would return Sept. 1, which is this Friday, the day after the preseason finale. The Rams have not received any similar indication from Donald, and Snead said he does not know if Donald would show up before agreeing to a contract.

The Rams won't truly know about Donald's Week 1 availability until he actually shows up at the facility.

"If you get him in this week, the goal would be for him to play a lot over the course of a 16-game season," Snead said. "So if you figure out that it's best to play a lot less Week 1, then that's the best thing to do."

Donald is owed less than $9 million in base salary from 2017 to 2018, which represents a sizable gap between him and the game's highest-paid defensive players. Broncos outside linebacker Von Miller signed a six-year, $114 million contract that guarantees him $70 million, and Dolphins defensive tackle Ndamukong Suh signed a six-year, $114.375 million deal that guarantees him nearly $60 million.

But those players received those contracts after five NFL seasons.

Snead would not say whether the Rams have offered to make Donald the game's highest-paid defensive player, but did say the front office has "definitely tried to come up with creative scenarios to get this done."

"It's a unique situation in that you have a player, and there is no, per se, finite end date in terms of the contract expiring," Snead added. "It's still a ways away, so, that's what we're trying to do."

Donald has been invited to the Pro Bowl after each of his first three seasons and has been named first-team All-Pro after each of the last two. His 28 sacks from 2014 to 2016 are four more than any other defensive tackle. Last year, his 31 quarterback hits led the NFL and his 17 tackles for loss were tied for the lead.

Snead believes Donald is "on pace to be a Hall of Famer," which few would argue.

Hall of Fame running back Eric Dickerson, who signed a one-day contract to retire with the Rams on Tuesday, considers Donald "the best player in the NFL on defense." Dickerson held out twice throughout his career and said it's "never easy on a player."

"I do believe that we will get him back," Dickerson said. "I don't know the specifics on contracts; that's not my deal. But I know this much: If I'm Aaron Donald -- and I've been in Aaron Donald's shoes -- he wants to come back here very badly. Trust me. I know how a football player thinks.

"You want to get paid, because you do this for a living. This is his job. I know he's not trying to be jealous with his football team. But like anything else, he has to take care of him, and also the team has to move forward, too, because it was the same thing when I was holding out. The team has to move on."