The Dolphins returned to practice after a four-day break, but cornerback Richard Marshall remains sidelined by a back injury that has sidelined him for two games.

Marshall was not in attendance Monday during the portion of practice open to the media. Marshall said last week that he hopes to play Sunday against the Jets.

Coach Joe Philbin declined to speculate on a timetable for Marshall’s return or say whether Nolan Carroll might continue to start even when Marshall is healthy.

Carroll has been generally solid in Marshall’s absence; the Bengals and Rams completed 7 of 13 passes thrown against him for 84 yards.

“Nolan has played well,” Philbin said. “We feel he’s making progress.”

The Dolphins announced running back Jonas Gray has returned to practice but is still on the physically unable to perform list. Miami has 21 days to decide whether to sign him. Gray suffered an ACL injury at Notre Dame last season.

This and that

Miami auditioned four undrafted rookies who were cut by other NFL teams in the past seven weeks: tight ends Chase Ford (Eagles) and Dominique Jones (one catch for the Colts this season) and safeties Cyhl Quarles (Patriots) and Sean Baker (Buccaneers). Ford played at the University of Miami.

• An NFL spokesperson said the league has not decided whether linebacker Koa Misi will be suspended in the wake of him pleading no contest to a felony battery charge. The NFL’s Greg Aiello said the matter will be reviewed under the league’s personal conduct policy.

• Offensive coordinator Mike Sherman said there’s “urgency” to get receiver Jabar Gaffney involved in the offense. “We have to push Gaffney forward,” he said. “He’s getting there. He’s going faster and making plays.”

Though the Dolphins like how Marlon Moore played as the No. 3 receiver against the Rams (including a touchdown catch), Sherman said Moore plays “a fair amount of special teams” and does not want to overburden him.

• Asked what player he would like to extract more from, Sherman named tight end Charles Clay, who has five receptions for 45 yards. “Clay is someone who can really help us down the stretch,” Sherman said. “I would like to see Clay step up and be a bigger factor in what we do.”

• Sherman said rookie tight end Michael Egnew, who hasn’t been active for a game, is “making progress” but “I can’t put a timetable on when he’s ready.”

Sherman said a “big part of his job will have to be special teams as well. Right now, he’s not quite there on that end.”

• Asked what player has improved the most, defensive coordinator Kevin Coyle cited cornerback Sean Smith. He said the new staff concluded during the offseason that he “had a lot of ability but wasn’t a consistent player. Too much variations in his performance. Now you’re getting a more consistent performer every week.”

• Houston Texans defensive linemen, especially J.J. Watt, are adept at batting down passes, and Coyle had the Dolphins cut up tape of all of those knock-downs to use as a teaching tool.

• Sherman called receiver Davone Bess “a small man with a big heart [who] plays big. There’s nothing I don’t like about him.”

Miami Herald sports writer Adam Beasley contributed to this report.