It's the second DL stint of the season for Saunders, who was previously sidelined from June 12-27 with inflammation in his right shoulder. Saunders was hitting .276 with six home runs and 28 RBIs in 65 games, including a .313 mark with five homers and 21 RBIs in 31 games since May 16.
Smoak was recalled from Tacoma after batting .284 with four doubles, three home runs and 11 RBIs in 19 games. He initially was sent down to the Rainiers on a rehab assignment after being placed on the DL with a strained left quad on June 11, but he remained in Tacoma when the Mariners chose to stay with Logan Morrison at first base.
But Smoak has heated up in the 10 games with Tacoma, hitting .325 with one double and two home runs. He's hit .632 (12-for-19) with two home runs in his past four games.
Smoak, who was back in the lineup at first base for Friday's series opener with the A's, hit .208 with seven home runs in 63 games with Seattle before going on the DL.
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.