​The Diamondbacks will designate right-hander Paul Sewald for assignment, moving on from the struggling reliever to clear room on the roster for newly signed right-hander Zack Littell.It is a stunning fall for Sewald, who less than two weeks ago still inhabited the closer’s role. He owned a 3.08 ERA on June 14 but allowed 18 earned runs in 12 2/3 innings since.Sewald converted 24 of 27 save chances for the Diamondbacks this season.The Diamondbacks agreed to a deal with Littell on Sunday, Aug. 10, and will finalize the signing on Monday, Aug. 11.He gives the club additional starting rotation depth and/or a potential long reliever in the bullpen. His status has not yet been spelled out by the club.The decision to designate Sewald was first reported by Arizona Sports.Rockies at Diamondbacks, 6:40 p.m., Cox, Ch. 34Diamondbacks RHP Michael Soroka (8-3, 3.07) vs. Rockies RHP Gabriel Hughes (0-3, 4.25).At Chase Field: Soroka has not pitched since June 19, the night he left his outing after one inning due to a glute injury. … At the time of his injury, he had been perhaps the Diamondbacks’ second-best starter behind LHP Eduardo Rodriguez. He has given up two or fewer runs in 12 of his 15 starts. … He made a rehab start last week with Triple-A Reno, giving up one run on three hits in four innings. His average fastball velocity (92.7 mph) in that start was down a tick from his season average (93.7 mph). … Hughes was the 10th overall pick in the 2022 draft out of Gonzaga. … He made his major league debut on July 3, tossing three scoreless innings in relief. He has started each of his other five games, logging a 4.73 ERA in 26 2/3 innings. … Hughes averages 92.5 mph with his four-seam fastball, which he throws 55.1 percent of the time. He has five other pitches: slider, changeup, curveball, sweeper and sinker.Coming upTuesday, Aug. 11: At Chase Field, 6:40 p.m., Diamondbacks LHP Mitch Bratt (1-1, 3.90) vs. Rockies RHP Tomoyuki Sugano (11-5, 4.51).Wednesday, Aug. 12: At Chase Field, 12:40 p.m., Diamondbacks RHP Merrill Kelly (8-9, 4.88) vs. Rockies RHP Ryan Feltner (4-6, 5.71).Thursday, Aug. 13: Off.Friday, Aug. 14: At Atlanta, 4:15 p.m., Diamondbacks RHP Brandon Pfaadt (6-1, 3.36) vs. Braves LHP Chris Sale (12-7, 2.20).This article originally appeared on Arizona Republic: Diamondbacks-Rockies updates. Paul Sewald designated for assignment