Gio Gonzalez seeks to duplicate his 2017 performance this season. (Jonathan Newton/The Washington Post)

WEST PALM BEACH, Fla. — Earlier this month, on one of those Grapefruit League game days that blend together after about a week, Gio Gonzalez unpacked a massive boombox at his locker. It came with shoulder strap so, naturally, after linking it to his phone via Bluetooth, the Washington Nationals left-hander threw the retro sound machine over his shoulder and lugged it around. He connected it to a microphone and had Wilmer Difo perform karaoke to reggaeton in the middle of the clubhouse at the Ballpark of the Palm Beaches. Teammates, clubbies and General Manager Mike Rizzo laughed and rolled their eyes at the unusual sight and thumping bass.

The show, about an hour before first pitch, was evidence of a veteran comfortable in his surroundings. Gonzalez is a proud son of Hialeah, Fla., but Washington has become home. He arrived via blockbuster trade in the prime of his career at 26. Off the field, he started a family and lives in the area year-round. On the field, he is one of just four remaining Nationals to play for each of the club’s four playoff teams; he tossed the first Nationals pitch in team playoff history in 2012; and he nearly won the Cy Young Award that same season, which will probably go down as the best of his career. Now, at 32, he is entering his seventh season as a National. With free agency looming this fall, it could also be his final one.

“I would love to have a big year with the team and with everything that’s going around, I would love to do that,” Gonzalez said. “I just got to stay healthy. That’s all I got to do.”

Staying healthy is Gonzalez’s most exceptional ability. Since joining Washington, Gonzalez ranks in the top 20 among baseball’s starting pitchers in starts (tied for eighth) and innings pitched (19th). He has been placed on the disabled list once in his career — in 2014, with shoulder inflammation, and he still managed to make 27 starts that season. While he is perhaps known more, fairly or not, for his laborious outings and playoff troubles than anything else in a Nationals uniform, Gonzalez also quietly became one of baseball’s most durable hurlers in an era when durability from pitchers is gold. For $53 million over the past six seasons and another $12 million due in 2018, that gold came at a bargain.

There isn’t a magic formula to the durability, according to Gonzalez. As he explained it, he believes sticking to a routine, which he said includes more stretching but has changed little otherwise over the years, and knowing how far to push himself has allowed for the consistency. But he did credit Livan Hernandez, the first ace in Nationals history, for helping instill the foundation for his endurance.

Gonzalez said he began working out with Hernandez, who led baseball in innings pitched three different seasons, and his older brother, Orlando, in Miami when he was 18. Along with several other ballplayers, they would run hills in the early morning at Tropical Park — the only hilly terrain in South Florida, Gonzalez noted — and Hernandez advised him to begin his offseason throwing program as late as possible. Gonzalez kept that in mind. Fourteen years later, he has made at least 31 starts in seven of his eight full major league seasons.

Instead, Gonzalez’s most significant recent adjustment has transpired between the lines. Once a hard-thrower who could get away with blowing fastballs by hitters, Gonzalez’s average fastball velocity has steadily diminished since his fastball averaged 94.2 mph, according to FanGraphs, in his first season with Washington. But he said it wasn’t until last season, when his fastball average dipped to 90.4 mph, that he began modifying his approach.

“Last year was a huge adjustment point,” Gonzalez said. “Last year I was actually pitching. I wasn’t trying to throw it. I understand that I have to be a pitcher. And that’s what it was. I don’t have to throw hard to get outs, and last year proved it. You just have to locate.”

The renewed approach, which included an increased use of his change-up and curveball, translated to Gonzalez’s best season since his first in Washington. After having his ERA escalate each of the four previous seasons, Gonzalez posted a 2.96 ERA, a career-best 150 ERA+ and a 1.179 WHIP in 201 innings across 32 starts during the 2017 regular season. A 3.54 walk rate, 4.24 xFIP and a minuscule .175 batting average against with runners in scoring position suggest he was the recipient of some good fortune, but results are results and Gonzalez was one of the National League’s best at run prevention last season. The performance culminated in a sixth-place finish in the NL Cy Young race for the newly crafty lefty.

“I don’t know what kind of lefty I am,” Gonzalez said with a chuckle. “I just want to be a healthy lefty, that’s it.”

He was, based on his regular season production, one of the best No. 3 starters in the majors. But he stumbled in the playoffs again, allowing three runs over three innings in Game 5 of the NLDS against the Chicago Cubs last October. The performance — and his impending free agency — left some wondering if the Nationals would acquire a starter to slot in behind Max Scherzer and Stephen Strasburg for this postseason and beyond.

But Washington settled last week for signing Jeremy Hellickson, who occupies a tier below and will compete for the No. 5 spot. For now, Gonzalez will occupy the same role, seeking to duplicate the results from last season in what could be the end at home in Washington.

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