Donald reported on the eve of Sunday's opener against the Indianapolis Colts at the Coliseum.
Rams fans are surely excited to see what Donald will do under newly appointed defensive coordinator Wade Phillips but will have to wait until at least Week 2 before they see No. 99 back on the field again. Coach Sean McVay ruled him out for the opener Friday.
Donald, 26, did not participate in the Rams' preseason activities as he seeks a contract extension.
Donald's representatives and the Rams will continue to work towards reaching a new deal, the team reported on their website Saturday.
Donald has not received a new contract, but the two sides will keep working toward one, the source told Schefter. The All-Pro defensive tackle is entering the fourth year of his five-year rookie deal and is slated to make $1.8 million in base salary this season.
But as the preseason wore on, Donald gave no public indication that he would report.
According to Michael David Smith of ProFootballTalk, the Rams will not play their star defensive lineman until he is ready for an actual game.
Tanzel Smart, a rookie sixth-round pick out of Tulane, is expected to start in Donald's place Sunday against the Colts.