SAN DIEGO -- The knuckleball is back; long live the knuckleball.

Before Saturday night, it had been more than two years since any pitcher had thrown a knuckleball in a Major League game. Then the Padres promoted right-hander Matt Waldron for a spot start -- and one of the sport's most beloved eccentricities returned.

Waldron pitched 4 2/3 solid innings in his big league debut -- a 2-0 loss to the Nationals on Saturday night at Petco Park. He allowed two runs and struck out two.

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But perhaps most notably: Waldron threw 13 knuckleballs, becoming the first pitcher since Baltimore’s Mickey Jannis in June 2021 to throw the pitch. It fluttered. It kept Nationals hitters off-balance. At one point, Padres catcher Gary Sánchez -- who had never caught a knuckleballer at any level -- flung his glove athletically to corral a particularly vicious knuckler to CJ Abrams in the fifth inning.

“It would move in, it would zag out,” Sánchez said. “I was just trying to do my best to catch it.”

Waldron isn’t a typical knuckleballer in the mold of a Tim Wakefield or an R.A. Dickey. The pitch is not his bread-and-butter. He threw more fastballs and sliders than knucklers on Saturday.

Given the results, however, it’s worth wondering if an uptick in knuckleballs could be in the offing for Waldron. He shied away from the pitch early, allowing homers to Jeimer Canderlario and Lane Thomas on his fastball. But when Waldron began to emphasize his knuckler -- he threw 11 of the 13 after the third inning -- he had success.

Waldron threw nine of his 13 knuckleballs for strikes, and Nationals hitters finished 0-for-3 on at-bats that ended with a knuckleball.

“Especially to lefties, I feel like it helped a lot, just to throw them the knuckleball, make them respect that,” Waldron said. “And then once they did, I could throw my other stuff. It felt pretty good out there that last inning.”

Waldron earned his promotion when the Padres made the decision to skip right-hander Michael Wacha in their rotation. Wacha, who is battling shoulder fatigue, played catch on Saturday afternoon, and, as of now, the team expects him to make his next start. 

As such, Waldron’s first stint in the big leagues will likely be short-lived. But after his surprise callup, he made a strong case for consideration the next time the Padres need to dip into their system for a starter.

“You’re pitching here in front of a full house in your first big league start,” said Padres manager Bob Melvin. “He gave up a couple homers but kept us in the game. … I thought he handled himself well.”

Said Waldron: “It was definitely a lot louder. It was surreal, and it was amazing. … All in all, it was pretty nerve-racking. But when you get out there, it’s the same game.”

Waldron has a 7.02 ERA at Triple-A El Paso this season, pitching in a notoriously hitter-friendly home ballpark in a notoriously hitter-friendly league. It’s worth wondering whether the knuckleball simply plays better at sea level. Waldron had posted a 2.84 ERA at Double-A San Antonio a year prior.

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Waldron is not a top prospect. He was an 18th-round selection by the Guardians in 2019, dealt to the Padres a year later as a player to be named later in the trade that brought Mike Clevinger to San Diego. In spring ’21, Waldron began dabbling with the knuckleball -- and was encouraged by the Padres. At first, Waldron was asked to throw the pitch almost exclusively, mirroring the usage of many past knuckleballers.

Eventually, Waldron found a different mix, using the pitch mostly to keep lefties off-balance. He threw it at a 21% clip Saturday. Perhaps that usage ticks up, considering the success he saw Saturday. But it won’t be his primary offering.

“I think it plays off my fastball better,” Waldron said. “I use it coming out that same tunnel.”

Waldron had begun throwing a knuckleball long before he began doing so professionally in 2021. He first developed the pitch in Little League, messing around with his twin brother, Mike. They liked the way it looked in video games. 

“[It started] just out of curiosity,” said Mike, who was on hand Saturday night and interviewed between innings by MLB’s broadcast. “It was one of those things that you're like, ‘Hey, that's pretty cool. We'll go ahead and see what we can do, throw it around.’

“It kind of became one of those fun pitches we'd throw around when we were at practice or something, just something to mess around with. To see it work at this level ... it's unbelievable, really.”