The Arizona Diamondbacks have reinstated pitcher Ryne Nelson from the injured list and recalled outfielder Alek Thomas from Triple-A Reno, the team announced Thursday.

The D-backs optioned pitchers Yilber Diaz and Blake Walston to Triple-A following Wednesday's game against the San Francisco Giants.

Nelson had been on the injured list since Sept. 14 with right shoulder inflammation.

The Diamondbacks will now have decisions to make for who will start in the rotation ahead of their final regular season series against the San Diego Padres. Merrill Kelly is scheduled to pitch Friday's game with Saturday and Sunday's starters yet to be announced.

Nelson rejoins the club as the team remains one game ahead of the Atlanta Braves for the final Wild Card spot in the National League with three games remaining in the regular season.

Nelson threw a 16-pitch bullpen on Saturday. He had been one of Arizona's most consistent starter before going on the IL, owning a 3.16 ERA in 79.1 frames over that stretch.

Thomas was activated by the Reno Aces on Sept. 17 after missing over a month due a oblique injury.

Thomas was sent down to Reno on Aug. 13, and a week later was placed on the injured list. He had five hits at the plate in his three games for the Aces before getting injured.

The D-backs originally optioned Thomas after his bat struggled to pick up rhythm across a month-long period in his return from a hamstring injury that had multiple setbacks. In 37 games, Thomas was batting .191 with three home runs and 17 RBIs.

Thomas returns as he fights for playing time in a crowded outfield of Jake McCarthy, Corbin Carroll, Lourdes Gurriel Jr., Randal Grichuk and Pavin Smith, the latter having been of the D-backs better hitters as of late, hitting .310 with six home runs and 19 RBIs in the month of September.