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A.J. Puk’s big arm has always sparked tantalizing projections for his big league future. However, health and control issues have been constant roadblocks on his path to success.

It’s still too early to declare that Puk is fully beyond those previous concerns. One month into the 2022 season, though, the 27-year-old left-hander is showing just why the A’s made him the sixth overall pick in the 2016 MLB Draft.

Puk has not allowed a run in six of his first seven relief outings, posting a 0.79 ERA across 11 1/3 innings. A key to the strong early showing has been his much-improved fastball command. Puk’s 1.59 walks per nine innings is by far the lowest mark of his professional career, having issued just two walks as opposed to 13 strikeouts.

His dominance was on full display against the Rays on Tuesday night. Entering the game in the sixth to hold a two-run lead, the electric lefty fired two scoreless innings, retiring all six batters he faced.

Puk quickly attacked each Tampa Bay hitter, throwing five first-pitch strikes and registering a pair of swinging strikeouts. Both punchouts came on his slider, a pitch that is proving to be nearly unhittable after making an adjustment to how he throws it.

During the final week of Spring Training, A’s pitching coach Scott Emerson suggested to Puk that he throw from the first-base side of the pitching rubber. This method is especially beneficial for left-handers with a sweeping breaking ball, such as Puk’s slider. Particularly against left-handed hitters, throwing from the first-base side of the rubber creates a better angle for the pitcher. In Emerson’s words, it allows lefties to “just grip it and rip it” for better sweeping action that covers the entire plate.

“It’s helped out a lot,” Puk said of the adjustment. “It’s given it a lot more depth. It’s been good so far.”

Puk’s numbers certainly back up his decision to make the change. Through Wednesday, opposing batters were hitting just .176 (3-for-17) with seven strikeouts against his slider. His swing-and-miss stats (47.5% whiff rate) with the slider show that he’s starting to master a filthy secondary pitch to complement his power fastball, which is averaging 96.1 mph this season.

Before the start of the season, A’s manager Mark Kotsay said he believes Puk can carve out a role for himself in the Major Leagues similar to that of Josh Hader, another big lefty who emerged as a multi-inning weapon for the Brewers and eventually established himself as an All-Star closer. A continuation of this performance by Puk will definitely keep him on that trajectory, with a chance to elevate to even higher-leverage situations.

“He’s found a delivery that takes the stress off his arm. His arm feels great. His recovery is great, and he’s pitching outstanding,” Emerson said. “I think building that confidence in his arm that he can let it rip and feel good about it is No. 1. As he goes out and puts up good outings, it’ll give him even more confidence.”