Lucas Giolito entered Monday with a 3.15 ERA for the White Sox. The Nationals traded him to Chicago in December 2016 with two other pitching prospects for outfieder Adam Eaton. (Nam Y. Huh/AP)
Sports columnist

When Lucas Giolito followed a 96-mph fastball with a devastating change-up that completely locked up Cody Bellinger, setting the Los Angeles Dodgers star down on strikes, it was a pronouncement not that he was back, but that he had arrived. “A year ago, I wasn’t thinking about being an all-star,” Giolito said that afternoon last week, before he took the mound in Cleveland as just that, an American League all-star.

This is not meant to be a lament of what might have been. Yes, it’s true, the Washington Nationals placed ace Max Scherzer on the injured list with a balky back, so Scherzer was unable to start Sunday’s series finale in Philadelphia and will be unavailable for the two games this week in Baltimore against the woeful Orioles. Sure, it would be great for the Nats if they had Giolito rather than, say, Austin Voth ready to step in when Scherzer’s out — or just be a regular member of an already dominant rotation.

Yet as the Nationals continue this crucial stretch, and as Giolito continues his first all-star season for the Chicago White Sox, understand that Giolito’s development couldn’t have happened as it did had he remained with Washington. Exploring the at-the-time circumstances and years-later outcomes of one of Nationals General Manager Mike Rizzo’s many trades, we can learn something about what could be coming at any time this month: a trade of a Nats player with potential down the road for someone who can help them get to the postseason right now.

“It was a relief,” Giolito said of the December 2016 deal that sent him, along with fellow pitching prospects Reynaldo Lopez and Dane Dunning, to the White Sox for veteran outfielder Adam Eaton.

The previous summer, Giolito had arrived on a Nationals team that had every intention of reaching the World Series. He was a 21-year-old right-hander who had been identified as the sport’s best pitching prospect, and he was burdened by that status. He bounced from the majors to the minors and back. He struggled with his mechanics, his results, his velocity. He started four big league games, was kept in the bullpen for September and turned in a 6.75 ERA over 21 1 /3 innings.

“It was tough, because obviously I wasn’t helping the team,” Giolito said in Cleveland. “I didn’t really feel like part of the team. I felt like I kind of ruined my first impression, and the confidence was down.”

The Nationals’ rotation was and is anchored by Scherzer and Stephen Strasburg, two of the most talented and driven pitchers in the game. In their different ways, they tried to bring Giolito along. I remember talking to Giolito at his Nationals Park locker, which was next to Strasburg’s, about some topic I considered innocuous during the summer of 2016. Strasburg overheard and muttered, “Giolito — keep it in the clubhouse.” Giolito instantly became less frank. Scherzer took Giolito on one of his grueling, between-starts runs. Giolito couldn’t finish it. The lessons were hard.

“He was 21 years old, and I don’t care how good you are,” Scherzer said. “When you’re young, you get to this level, you get exposed. . . . I feel like he was a guy that really needed to learn the game and work at his craft. Failure wasn’t necessarily a bad thing for him. He’s taken his licks. He’s gotten punched in the face. And yet, he’s come back better.”

The better, though, was far from immediate. And that’s important, even as Giolito entered Monday’s start in Kansas City — his first since his scoreless inning in the All-Star Game — with a 3.15 ERA and a gaudy 11-3 record. To become an all-star, Giolito not only needed to get over the “relief” from the trade. He had to endure one of the worst seasons for a starting pitcher in recent memory.

Last year, Giolito’s first full season in the majors, the rebuilding White Sox granted him 32 starts. He turned in an ERA of 6.13, the worst of any pitcher with enough innings to qualify for the ERA title in 10 years. He walked 90 batters, not only the most in either league, but the most in baseball since 2012.

“My in-game confidence was like a roller coaster,” Giolito said. “I would start a game, give up a couple base hits, walk a guy, and I was like, ‘Oh, man.’ It felt like the world was crashing around me.”

Last year’s Nationals finished 82-80 and were a non-factor over the final month of the season. But the year didn’t begin that way. It began with the hope not only of building on consecutive division titles, but on pushing past the first round of the playoffs for the first time. A team with those goals can’t give 173 innings to a pitcher who is posting an ERA north of six. It just can’t.

“If you come up and you’re still working on things and still developing and you need experience,” Giolito said, “it’s definitely easier on a rebuilding team.”

This goes for any number of players the perpetually win-now Nationals have dealt away in recent seasons. Left-handed reliever Felipe Vazquez has made the past two All-Star Games as a Pittsburgh Pirate, but when the Nats dealt him for closer Mark Melancon in 2016 (when Vazquez’s last name was Rivero), he had a 4.53 ERA. He was close, just not close enough to helping a contender.

Young pitcher Jesus Luzardo was the key figure in the trade that brought relievers Sean Doolittle and Ryan Madson in 2017 from Oakland, where the A’s had time to wait and the Nats didn’t. This past winter, the Nats needed catching — immediately — so they sent two prospects to Cleveland for Yan Gomes. One of those players, outfielder Daniel Johnson, ended up in the Futures Game last week. Getting quality requires giving quality, and the Nats have done that — repeatedly.

Thus, it will always and forever be tempting to compare Giolito’s contributions to the White Sox to Eaton’s contributions to the Nats. Right now, with Eaton’s on-base-plus-slugging percentage (.746) at a six-year low, it doesn’t look great. But that in-the-moment evaluation doesn’t consider the journey Giolito took to be an all-star.

“I always maintained a certain level of ‘I’m going to get through this,’” Giolito said. “ ‘It sucks now, but this is going to benefit me in the future. It’s going to make me mentally stronger. I’m going to learn everything I can from it.”

There’s the Nats’ conundrum. They need talented players from their own system to replace players as they leave or get injured. But they don’t have time to watch players grow stronger through failure, regardless of how promising they are. It’s not only hard for a franchise to try to win every single season. Just the trying has an impact on a team’s roster, and the fan base, years later, can say, “Why don’t we have that guy anymore?”