NEW YORK -- Still bleary-eyed after a flight from the West Coast hours earlier, Clay Holmes stood in a checkout lane of a Pittsburgh Target last July, clutching bottles of water and a fresh tube of toothpaste. He felt his cell phone buzz and, recognizing the number, thumbed a green button to accept the call.

Life was about to change.

Holmes heard the voice of Pirates general manager Ben Cherington; the call did not come as a surprise, considering the perennially rebuilding Bucs’ situation. Cherington did not waste words, informing the right-hander that he’d been traded to the Yankees and should get back on a plane quickly. Holmes spun and strode through the store aisles, searching for a razor.

“I was honestly just waiting to hear what team I was traded to,” Holmes said. “I was pretty pumped that it was the Yankees, just for the history and knowing some guys here. I couldn’t wait to get over here, knowing I was going to a place where people expect to win.”

The beard that Holmes had worn in Pittsburgh disappeared down a sink drain, and soon he was off, too, embracing a new chapter. Holmes owned a 5.57 ERA in 91 career appearances; there were no back-page announcements or headlines to trumpet the acquisition, lost as white noise behind the Yanks’ July moves for first baseman Anthony Rizzo and outfielder Joey Gallo.

But the Yankees saw something to unlock within Holmes. Shawn Hill and Brandon Duckworth, former pitchers-turned-scouts, both lobbied for his acquisition. Encouraged by pitching coach Matt Blake to trust his power sinker and attack the strike zone more, Holmes responded to his new surroundings, posting a 1.61 ERA in 25 appearances.

It would be just an appetizer for this main course. Thanks mainly to that sinker, a pitch manager Aaron Boone calls “one of the nastiest in baseball,” Holmes has developed into a likely All-Star and a dominant late-inning force.

“I don’t remember it being that good when we were drafted, but it’s right up there as one of the best pitches in baseball, for sure,” said Gerrit Cole, a Pirates teammate of Holmes’. “When he came over, it was about throwing strikes, hammering the strike zone. He really hasn’t looked back. I think he’s starting to have some self-awareness on nights when he needs to challenge guys, and when he’s feeling really good, he can put the ball exactly where he wants to.”

Holmes’ sinker is released from a higher arm slot than the average big leaguer, seeing improvements from Blake, the club’s development gurus and Holmes’ interest in pitch metrics to track movement. Complementing the sinker by scrapping his curveball in favor of a slider, Holmes has generated ground balls at a historic rate.

“He’s a video game,” Jameson Taillon said. “He’s one of those guys you would have bet on years ago to figure it out and become this type of guy, so I’m not super surprised at what he’s doing. But it is fun to watch.”

Holmes’ 82.4 percent ground ball rate through Sunday would be the highest in the Majors since 2002, when FanGraphs began tracking such data; the record for a reliever over that span was set in '16 by Zack Britton, who had an 80-percent ground ball rate while pitching to a microscopic 0.54 ERA and leading the AL with 47 saves.

“I’ve just started learning my best sinker and trying to throw that one more often,” Holmes said. “The feel has definitely come along and I’ve been able to throw it to both sides of the plate if I need to. It’s been a combination of things, but first is being in good counts with it so I can let the action do the work.”

At a -13 run value, Statcast measures Holmes’ sinker as the fourth-most valuable pitch this season, behind Nick Pivetta’s four-seamer (-15), Corbin Burnes’ cutter (-14) and Dylan Cease’s slider (-14). Put simply, batters haven’t been able to solve Holmes, who ranks in the 99th percentile rate in barrel rate allowed. When the Rays finally snapped Holmes’ 31 1/3-inning scoreless streak on June 20, the runs came on two softly hit balls that did not leave the infield.

“The infield defense has been so good this year, especially for a ground-ball guy like me,” Holmes said. “To have the trust that I can put the ball on the ground and, more times than not, they’re going to get it, it’s been huge.”

Holmes’ streak of 29 consecutive scoreless appearances from April 9-June 18 shattered a Yankee record held by Mariano Rivera, who kept opponents off the board in 28 straight outings from July 22-Oct. 22, 1999. Holmes said that he considered it “pretty cool” to be mentioned in the same sentence as the great Rivera, “even if it’s just for a simple scoreless innings streak.”

Much as Joe Torre then felt comfort in calling the bullpen for Rivera, so does Boone, creating a wrinkle in how the Yankees will handle the return of Aroldis Chapman -- the club’s closer for most of the past six seasons, but perhaps no longer.

Chapman began the year in the closer’s role; he was 9-for-9 in save opportunities, though the 34-year-old hardly showcased the clean dominance that Holmes enjoyed since taking over in late May, when Chapman landed on the injured list with a left Achilles injury. Chapman said recently that Holmes “deserves the role as closer right now.”

Boone has not gone that far, leaving some wiggle room in how he will handle Chapman’s pending return. Chapman made the second and perhaps final appearance of his Minor League rehab assignment on Sunday for Double-A Somerset, the same afternoon that Holmes pitched a scoreless ninth inning in the Yankees’ 6-3, 10-inning win over the Astros.

The working theory is that Holmes could be used against the toughest parts of lineups while still receiving save opportunities -- Boone uses the example of a hypothetical one-run game against the Blue Jays, where George Springer, Bo Bichette and Vladimir Guerrero are due up in the eighth inning. In that situation, he’d deploy Holmes, then figure out the ninth.

“I kind of laugh about the continued questions about Chappy and Holmes,” Boone said. “Clay Holmes has become an absolute beast, and hopefully Chappy is healthy and gives us another guy that can really help shorten the game.”

That makes sense, and though it may prove more challenging to execute in actual practice, we all understand that plans can change. After all, Holmes once entered that Pittsburgh Target store in search of toiletries and essentials. He reached the parking lot destined to become the Yankees’ seemingly-automatic relief ace.

“I knew I was onto something, especially at the end of last year,” Holmes said. “I really stayed on things in the offseason because I knew that was where I needed to be. You definitely take a second to appreciate it, but you’ve also got to keep moving forward and continue to take care of business; keep doing the things that put you in position to have success.”