Since Saunders got hurt, the Mariners traded for center fielder Austin Jackson and right fielder Chris Denorfia, so there appears less need to rush the 27-year-old back until he's fully healthy. Denorfia and veteran Endy Chavez have been splitting time in right field in a platoon situation that has been working well, with Chavez hitting .276 and the right-handed-hitting Denorfia hitting.320 over his last eight games after a slow start.
Saunders has hit .276 with six homers and 28 RBIs in 65 games for Seattle and is a strong defender, but he's on his second DL stint this season and manager Lloyd McClendon wants him to be right when he returns.
"He's working it out, he's trying to get back," McClendon said. "We knew there would be some rust. That's why you have the 20-day rehab. He's trying to get himself sharp and ready to get back here."
Saunders began his rehab assignment on Aug. 7, so the Mariners have until Aug. 27 before they need to make a decision. Minor League rehabs for position players can be a maximum of 20 days.
With James Jones optioned back to Tacoma on Monday to make room for starting pitcher Roenis Elias, Seattle is going with four outfielders for now in Dustin Ackley, Jackson, Chavez and Denorfia, though Logan Morrison played right field on Monday with no DH spot available in the Interleague road game.
If Saunders returns before Sept. 1, when rosters can be expanded beyond the 25-man limit, it will require a tough roster decision for a club that's been carrying an extra reliever and would likely need to make a move in the bullpen.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.