Baseball in March is often defined by early-game substitutions, unfamiliar names on backs of jerseys and games that have little to no meaning. All of that is okay; spring training is necessary. But, for Merrill Kelly, March baseball has looked quite different.

For a little under two weeks, he was, in a sense, no longer a Diamondback. He was a member of Team USA. And, on Tuesday, instead of pitching in a non-televised game at Salt River Fields in front of 6,000 fans, Kelly started the World Baseball Classic championship game against Team Japan, with over 36,000 fans in attendance and nearly five million Americans tuning in.

“It was incredible,” Kelly said, “from start to finish, just being able to be in that environment and being around the guys that I was around.”

Kelly’s baseball journey is remarkable. After hitting a wall in the Tampa Bay Rays organization in 2014, he signed with the SK Wyverns of the Korean Baseball Organization and pitched there from 2015-18. The Diamondbacks liked what they saw and brought Kelly back to the states, signing the Arizona State alum to a big-league contract prior to the 2019 season. On Tuesday, Kelly pitched on one of the biggest stages baseball has to offer.

“If you would have asked me if I thought I’d be on that team, much less starting the championship game against Japan … five years ago or even four years ago when I first got here, I’d never in a million years thought that that would even be an opportunity for me.”

Now that he is back with the Diamondbacks, Kelly is being forced to step back into the reality of Cactus League baseball. He will take the ball on Sunday afternoon against the Milwaukee Brewers at American Family Fields of Phoenix, a ballpark that holds 10,000 fans.

“It’s a little disappointing coming back and throwing in a spring training game after an environment like that,” he said. “It’s gonna be a little different.”

Nonetheless, Kelly said that his experience in the WBC did help him prepare for the large crowds that he will encounter soon. The Diamondbacks open their season next week in Los Angeles at Dodger Stadium, and Kelly is lined up to start one of those games.

“Opening night, the first couple nights in L.A. are gonna be probably just a similar experience,” he said. “They put on a good party over there.”

Unfortunately for Kelly, his enjoyment of the WBC comes more in spite of his performance than because of it. In his first outing on March 15, Kelly went three innings against Colombia, allowing two runs on four hits with two walks and one strikeout.

It was not his best outing, particularly given that Colombia’s lineup featured only a few major leaguers. Nonetheless, his teammates picked him up, and Team USA ultimately came away with a 3-2 win.

In Tuesday night’s championship game, Kelly was yanked after just 1 1/3 innings, allowing two runs on three hits with two walks and a strikeout. Kelly was sitting at 36 pitches when Team USA manager Mark DeRosa made his way to the mound.

“It was a little surprising,” Kelly said. “But I recognize that it’s the nature of the beast in a tournament like that. You gotta do what you think you gotta do to win that one game because there’s there’s obviously no tomorrow.”

Among those watching the game were Diamondbacks manager Torey Lovullo and assistant pitching coach Barry Enright. They understood the decision to pull Kelly from the game, but they also knew that a 36-pitch outing in his second-to-last start before Opening Day was going to keep him from being fully stretched out for his first start of the season.

“It was a discussion that Barry and I had via text after Merrill was taken out of the game,” Lovullo said.

Enright asked Lovullo if he wanted to reach out to Team USA coaches about having Kelly throw another 40 pitches in the bullpen.

“I said not a chance,” Lovullo recalled. “There’s no way I’m gonna do that, and it didn’t look like Merrill wanted to either.”

As a result of Kelly’s short outing, the Diamondbacks plan to take it slow with his workload. Lovullo said they would like to get him into the 60-65 pitch range in his final spring training start on Sunday, followed by roughly 85 pitches in his first start of the season.

Another challenge Kelly faces as a result of his participation in the WBC is readjusting to the pitch clock, which was not used in any WBC games. “It’s definitely a consideration that I had going into the tournament,” he said. Kelly pitched in only one game with the pitch clock before joining Team USA.

While Kelly said that is not too worried about it since he works relatively quickly, he did share some concerns over how the pitch clock might have adversely affected some of the best moments of this year’s WBC.

The most iconic moment of the whole tournament was arguably when Los Angeles Angels outfielder Mike Trout, who played for Team USA, faced off against teammate Shohei Ohtani, who represented Team Japan. The much-anticipated matchup happened at the perfect moment: with two outs in the ninth inning of Tuesday’s championship game and Japan holding onto a 3-2 lead.

During the at-bat, a certain question kept coming to Kelly’s mind: “How are we possibly going to put a pitch clock on a situation like this?

“If you put a time on it and have it be over a lot quicker than it was,” Kelly said, “I think [that] is gonna be an interesting pill to swallow for a lot of baseball fans. The anticipation of each pitch in that at-bat was part of what made that at-bat so special.”

Even worse, he wondered, what would have happened if the game had ended on a pitch clock violation?

“It would be a real shame if a game like that, in a situation like that, were ended on an automatic strike or an automatic ball. The whole point of that experience was to see who was going to come out on top, right? If Ohtani was going to strike him out or if Trout was going to hit a home run.

“If you ended that game on Trout not getting in the box by eight seconds, a lot of people would be up in arms with it … in my opinion, as they should be.”

For the moment, the pitch clock has yet to ruin any iconic baseball moments. But it is possible that it could, whether that is during this 2023 regular season, the postseason or, potentially, in the 2026 WBC, should Major League Baseball decide to implement it.

Regardless of what rules are implemented during the next iteration of the tournament, though, it appears that Kelly will be encouraging his teammates to participate.

“If you’re a baseball player at this level and you really love what you do, I don’t see a reason why you wouldn’t be a part of that,” Kelly said. “I pitched in the the Korean Series in 2018. That was 30,000 people in Seoul, but, I mean, it doesn’t even hold a candle to what these games were.

“When you add in the mix of countries versus countries and best versus best, there’s a whole different animal, whole different aspect of what it means, of what each pitch, each at-bat, each inning really means to each and every guy.

“It was an experience that I’ve never been a part of and maybe never get to experience again, but I’m forever grateful and honored.”

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Top photo: Rhona Wise/USA TODAY Sports