Red Sox place Hansel Robles on injured list, option Hirokazu Sawamura; Ryan Brasier, Phillips Valdez recalled from Triple-A Worcester

Robles last pitched in Sunday’s win over the Mariners before experiencing back issues while the Red Sox were in Chicago. Through 16 relief appearances this season, the 31-year-old right-hander has posted a 2.65 ERA and 5.20 FIP with 11 strikeouts to six walks over 17 innings pitched out of the bullpen.

Since his stint on the injured list is retroactive to May 25, the soonest Robles could return to action would be Thursday June 9, when the Sox take on the Angels in Anaheim.

Sawamura, meanwhile, has pitched to the tune of a 3.60 ERA and 3.47 FIP with 13 strikeouts to six walks across 18 appearances (15 innings) so far this season. The Japanese-born righty has been most effective when inheriting runners on the basepaths, but — at the same time — has fallen down Alex Cora’s depth chart.

Because he has pitched three times in the last four days, Boston elected to send Sawamura down to Worcester while adding fresh reinforcements in Brasier and Valdez.

Both Brasier and Valdez opened the 2021 season in the Sox’ bullpen but were optioned to the WooSox at separate points this month. Brasier, who was sent down on May 20, made two scoreless outings for Worcester. Valdez, who was sent down on May 2, produced a 1.17 ERA in six appearances (7 2/3 innings) for the affiliate.

The Red Sox did not need to use their bullpen as Nathan Eovaldi tossed a complete game in the day cap of Saturday’s twin bill. That could change in Game 2 with Winckowski making his first career start at the big-league level.