The pitch looked like any other, just one in a summer of thousands, a humming four-seam fastball that clipped the outside corner for strike one.

But it wasn’t for Kyle McGowin, not even a little bit, so the 26-year-old pitcher kept one eye on the baseball as he walked back to the rubber. Catcher Pedro Severino bounced it toward the Washington Nationals’ dugout and into the hands of clubhouse manager Mike Wallace. He flipped it to a field-side authenticator, who examined the ball, placed a shiny silver sticker on it and tossed it back to Wallace a few seconds later.

Then Wallace, the Nationals’ keeper of keepsakes, inscribed the ball with a blue pen, encased it in a plastic box and put it on a wooden shelf in McGowin’s locker. That sticker, with a searchable serial number on it, confirms that on Sept. 5, 2018, inside Nationals Park, in the sixth inning against the St. Louis Cardinals, Kyle McGowin threw his first pitch as a major leaguer.

And the ball he did it with, no matter how many more he throws, or how many more seasons he plays, is his to keep.

“I had another pitch to throw right after, my second pitch, but I couldn’t help but watch Pedro toss it aside,” McGowin said. “That was my ball, I knew it, and a lot of work went into getting it.”

This September, like all baseball Septembers, will include a lot of first pitches, first strikeouts, first hits and first home runs, all sent into the dugout to be stashed and saved. Once rosters expanded Sept. 1, the league became dotted with young prospects and aging minor leaguers and rookies with few stats, if any. Last Tuesday alone, at Citizens Bank Park in Philadelphia, the Nationals set aside balls for Spencer Kieboom’s first career home run, Erick Fedde’s first career hit and McGowin’s first career strikeout.

As the Nationals skid toward a disappointing finish, those balls are some of the few bright spots of a dim summer. Most will want to forget these 30 days marked by rain and reminders of what this Nationals’ season was supposed to be. Yet for McGowin or Kieboom or rookie reliever Austen Williams, some small moments always will be remembered, for what this month did for their careers, and what those baseballs will mean for the rest of their lives.

“It’s the kind of thing that when you get a bit older, you look back and you really appreciate it, that you have that baseball as a memory,” 31-year-old closer Sean Doolittle said. “You pitched in a major league game, or you hit in a major league game, and no one can ever take that away from you. It’s pretty damn cool.”

The baseballs for Doolittle’s first pitch and strikeout are in a storage unit in Arizona. He and his wife have bounced around so much, including a cross-country trade from the Oakland Athletics to the Nationals last season, that Doolittle likes knowing exactly where his prized possessions are. They recently bought a house in Chicago and the plan is to organize all of it in one place this offseason.

But Doolittle has one piece of his career with him all the time. It is the “joke ball” from his first appearance with the Athletics in 2012, when a few veterans thought it would be funny to prank him with mock inscriptions. For any first strikeout baseball, the pitcher’s name, hitter’s name, final score and date are written on it. For Doolittle’s fake one, they spelled his first and last name incorrectly (”Shawn Dolittle”), the hitter’s name as “Nelson Cruise” (it’s Nelson Cruz) and put the wrong date and score.

“I got back to my locker after the game - I’m all excited because I see the ball there - and then I’m like, ‘Wait a minute, it’s all wrong. My name is spelled wrong, that’s not the score, what’s going on?’” Doolittle said through a big smile. “I’ve always kept that ball close because of the story. It’s the story that matters.”

McGowin’s path includes six summers in the minor leagues, uncertain whether he would ever make it, a self-help book called “Mind Gym” that helped him settle his thoughts and not put so much pressure on each pitch. Then he threw that first-strike fastball against the Cardinals, and finally, it all felt worth it.

Williams, a 25-year-old pitcher, was once steeped in similar doubt. In the summer of 2015, his fastball velocity dipped from the mid-90s to the high-80s. He remembers standing in the outfield, of some small ballpark in some small town, and forgetting how to throw. This time last year, he finished his season with the Class A Potomac Nationals and the majors felt further away than ever. Then he pitched two innings for the Nationals on Sept. 2, notched his first career pitch and strikeout, and had two baseballs waiting for him after the game.

Yet there was one small problem. Williams’s first pitch was fouled into the Nationals Park seats by Milwaukee Brewers third baseman Mike Moustakas. The young fan who caught it used a sharpie to sign his own name, meaning the Nationals could not properly authenticate it. Williams instead was given his second pitch, a high slider for ball one.

“If you want to keep somebody’s first pitch, the key is to sign it right away with your own name I guess,” Williams said while laughing. “That was a pretty savvy move by that kid.”

And there was outfielder Andrew Stevenson’s first homer, on a damp night in late August, in his first major league appearance of 2018. That was the day the Nationals traded Daniel Murphy to the Chicago Cubs and Matt Adams to the Cardinals, creating two open spots on their roster. Stevenson got the news in Syracuse and was told to rush to Washington in case he was needed against the Phillies. He drove six hours non-stop through a storm and arrived at Nationals Park during a rain delay. Manager Dave Martinez told him to stretch and stay ready. Then in the sixth inning, he smacked a slider over the fence in left-center field.

“Whenever I look at this ball, I will immediately think back to that night,” Stevenson said as he ran the case through his fingers, Wallace’s skinny handwriting spelling out “2 RUN PINCH HIT HR” between the seams. “It was so crazy, the driving on the highway, the rain, pinch-hitting in that spot. But I made it.”

Stevenson is in a temporary apartment and has no clue where he’ll be in a year, or even a month, from now. That’s the life of a fringe major leaguer. There is a wide gap between reaching a goal and reaching the goal. And since he doesn’t want to lose that home run ball as he travels from one opportunity to the next, Stevenson soon will send it home to Lafayette, Louisiana, for safe keeping.

But he dreams of one day having his own big house to display it in. They all do, Stevenson, McGowin, Williams and every other player experiencing the major leagues this September. Williams is related to longtime starter Jon Lieber, who pitched for four teams, was an all star in 2001 and won 131 games across 14 seasons. Growing up, Williams visited Lieber’s home in Mobile, Alabama, and loved the upstairs room with all the balls and bats and other remnants of a long career.

There was Lieber’s first pitch ball. And his first strikeout ball. And a broken bat signed by Mark McGwire that Williams will never forget. To Williams, that room was everything - success covering the shelves and walls.

“Having the first balls, it’s amazing, you can’t really describe the feeling,” Williams said. “But I really hope it’s only the start, that I have a whole career of things to see and collect and save. This just makes me want that even more.”

jesse.dougherty@washpost.com

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