Verdugo made an emergency start Tuesday night, after originally scheduled starter Everett Teaford was forced into relief on Monday. The outing was Verdugo's Major League debut, and it did not go well. He allowed six runs and exited the game after just 1 2/3 innings.
Bueno, a reliever, had a two-game stint with the Royals earlier this season, allowing one run on two hits in two innings. At Omaha this year, Bueno posted a 2.88 ERA in 31 games with 46 strikeouts in 50 innings for the Storm Chasers.
After Verdugo's brief outing, the Royals used five pitchers out of the bullpen on Tuesday. After the game, manager Ned Yost said his 'pen was in fine shape for Wednesday, but Bueno's arrival will provide more depth.
"What we like about him is that he throws strikes. He competes and throws strikes. And he's left-handed," Yost said. "We used Tim Collins [Tuesday] night for two innings, and we've got [Jose] Mijares, who's ready to go. [Mijares] threw three days in a row and just had two days off. He's ready to go. So we've got a pretty good tandem down there. With a bunch of left-handed hitters in [Seattle's] lineup, we'll be able to mix and match a little better with [Bueno] down there right now."
Vinnie Duber is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.