Oviedo was the main piece going to Pittsburgh when the Cardinals acquired pitchers Jose Quintana and Chris Stratton at the trade deadline last season.
He showed some promise with the Cardinals as he was one of several rookies that pitched for St.Louis in the COVID shortened 2020 season. The experiment of trying him as a starter did not go well, in 18 starts total in '20 and '21 he did not record a win. Partially because he struggled with giving up runs (5.08 ERA in 18 starts), and he struggled with throwing strikes (49 walks in 87 innings) it was difficult for Oviedo to get through 5 innings which qualifies you for a win because he could not record quick outs.
Last season Oviedo was put in the bullpen when he was recalled from the minors and his numbers were improved. He would get his first career win, his walks were down and strikeouts were up, more than one per inning before he was traded to Pittsburgh.
When Oviedo got to the Pirates they put him back in the rotation and he was solid in a handful of starts last year. This season however he has gotten off to a slow start. In 9 starts he has a 4.69 ERA which is the highest ERA currently in the Pirates rotation, and he has given up 51 hits in 48 innings. The season is still young so Oviedo should get more chances to turn things around, but he is only 25 years old, and he obviously still has some developing to do. With Quintana no longer a Cardinal their main piece in that trade is gone. Oviedo can decide ultimately who benefits the most from this in-division trade.