WASHINGTON -- The Nationals called up right-hander Joe Ross from Triple-A Fresno prior to Friday night’s 4-3 win in the series opener vs. the Braves, adding an extra arm to aid a bullpen that has been taxed in recent days. Infielder Adrian Sanchez was optioned to Double-A Harrisburg as the corresponding roster move.

Washington played three games in the past two days to finish off a sweep of the Phillies, and a short start from Erick Fedde in Thursday’s 7-4 win forced manager Dave Martinez to use multiple relievers for the second consecutive day. Even though the Nats have not named a starter for Sunday’s series finale, Ross has likely been called up as insurance out of the bullpen for now.

Since returning to Fresno near the end of May, Ross had made his return to the starting rotation after a stint as a reliever in the big leagues earlier this year. At Triple-A, he made four starts and posted a 2.65 ERA with 10 strikeouts and three walks over 17 innings. In his most recent outing on Monday, Ross threw five scoreless innings.

Sean Doolittle, Tanner Rainey, Wander Suero and Javy Guerra had all pitched two days in a row, creating a need for fresh arms in the bullpen. Ross did not pitch Friday, but the Nats did use four relievers, including Guerra and Suero, who pitched for a third straight game to earn his first Major League save.

The Nats attempted to convert Ross into a reliever to start the season, but the experiment did not go as planned. In 16 outings, he compiled a 9.22 ERA with just 12 strikeouts and eight walks over 13 2/3 innings.

So for the next few days, Ross could provide some extra depth in the bullpen and still be a candidate to make a spot start on Sunday.