TORONTO — The first four pitches out of Cionel Pérez’s hand Sunday evaded the zone, but it was the fifth — a slider — that turned out to be all Pérez required.

The Orioles relief pitcher inherited the most difficult spot Sunday, and he made it more difficult by walking the first batter he faced to load the bases in the sixth inning. But if there’s anything that emphasizes the Pérez of this month compared to the Pérez of last month, it’s the slider he knew he could turn to in the biggest moment.

Kevin Kiermaier chopped it to shortstop, beginning an inning-ending double play that proved pivotal in Baltimore’s eventual sweep of the Toronto Blue Jays, their first at Rogers Centre since 2005.

“It’s extremely important to get that pitch going,” Pérez said through team interpreter Brandon Quinones. “It’s been coming along nicely now over the second month of the season, to get it with bigger movement.”

The improvement to Pérez’s slider, as well as his entire arsenal, hasn’t involved a change of grip on the baseball or any alteration with his wrist movement upon release. Instead, Pérez has overcome a difficult beginning to the year through a small mechanical adjustment that took pitching coach Chris Holt a large sample to pinpoint.

The issue at play over the first 15 or so appearances for Pérez came down to timing. When his left foot would begin his push-off, Pérez’s torso and head moved forward more quickly than they should’ve. It left him off balance just enough that, when his right foot planted, his body was ahead of his arm.

The result was an inability to locate his pitches with exactness, leading to 21 hits and eight walks off Pérez in his first 12 innings.

“My mechanics were out of sorts and felt a little off at times, and it would throw everything out of sorts,” Pérez said. “My command wasn’t always there, or the way I wanted it to break wasn’t always there.”

In that way, Pérez looks more like his old self — the flame-throwing left-hander who burst onto the scene as a reliever last season with Baltimore, whose slider offers a knee-buckling alternative to the lively fastball.

Since discovering the smallest of discrepancies in delivery between 2022 and 2023, going frame by frame on video even to notice a difference, Pérez feels the confidence swelling on the mound. After allowing seven runs amid that flood of baserunners in his first 12 innings, Pérez hasn’t permitted an earned run in his last 6 1/3 frames, including Sunday’s tightrope situation.

“It seems like he’s throwing the ball with a lot of confidence and conviction and fire again,” Holt said. “He’s a competitive-fire guy. When he’s doing that, he’s at his best. I can see that from a gamesmanship and mental approach. He’s starting to come back on with how he’s breathing fire and throwing the heck out of it.”

The turnaround began in Atlanta this month, when Pérez recorded four outs against the top lineup in the National League. And even though he allowed a double in the 12th inning the following day — bringing home the winning run — it was one blemish in a month that otherwise has been nearly flawless.

Part of Pérez’s challenge this season is giving hitters a different look than they’ve seen before. In his first year with Baltimore, the 27-year-old found the most success of his career with a 1.40 ERA in 66 appearances. He did it primarily through his fastball and slider.

Toward the end of last season, Holt encouraged Pérez to reintroduce the curveball to his repertoire. Pérez threw it in 2018 with the Houston Astros, when both he and Holt were with the organization. By adding it back, the starter-turned-reliever has a four-pitch mix to keep hitters off balance.

“It just provides another method of showing hitters different angles,” Pérez said. “The fastball can rise a little bit. The slider can be in on a right-handed hitter and move away from a left-handed hitter. So the curveball gives me a way to have a pitch that just drops to the mound and give hitters a different look.”

At 16%, Pérez is throwing his curveball more than ever, but it’s dependent on the right matchup (he uses it primarily against right-handed hitters, with 80% of his curveballs coming in those situations).

His four-seam fastball usage is down seven percentage points, and his slider usage is down 10 percentage points from 2022. The results, though, are encouraging, particularly now that Pérez has improved the movement on his slider.

“Love the way Cionel is throwing right now,” manager Brandon Hyde said. “To me, this is what he looked like last year. Huge for us, getting him and Danny [Coulombe] going, that’s two really good lefties. We’re going to need both of these guys, but nice to see Cionel kind of command the ball like he did last year.”

Getting back to this point took slow-motion video, a slight mechanical tweak to maintain his balance better and a belief that the early results against Pérez weren’t going to derail his entire campaign. It’s a major boost for Baltimore’s bullpen, and Pérez came through in one of the biggest spots Sunday because of it.

“Not going to lie, it feels good,” Pérez said. “Now, stepping on the mound, you start to feel a lot more confident. You start to feel a lot better and a lot more comfortable.”

andy.kostka@thebaltimorebanner.com