Gio Gonzalez allowed five runs in five innings in Washington’s 8-0 loss to the Braves. (Patrick Mcdermott/Getty Images)

Gio Gonzalez isn't like the other Washington Nationals starters, who might utter a barely audible "hello" on days they pitch, if they say anything at all. He was under the weather Tuesday, but he still chatted with a few of the young teammates near his locker, then a coach or two, then offered pats on the back to a reporter here and a teammate there — to whoever got near enough to receive one, really.

A few hours later, Gonzalez struck out Braves center fielder Ender Inciarte for the first out of the Nationals' 8-0 loss to Atlanta. In so doing, Gonzalez crossed the 180-inning threshold at which his 2018 club option vests. Barring a trade, the friendliest National, an oft-overlooked keystone of the clubhouse and rotation, will be back next season.

Gonzalez did not appear to want to discuss the option, which was part of a team-friendly deal negotiated by his former agents at ACES, before he hired Scott Boras .

"We'll just focus and continue to strive to get better," Gonzalez said of his future with the Nationals. ". . . We're not there yet so we got to focus."

Still, Gonzalez's status is the most important takeaway from an otherwise uninspiring evening from the newly crowned National League East champions, who fell to 88-56 with a performance that reeked of a metaphorical hangover, if not a literal one.

"I was hoping [we wouldn't have a letdown] because we had a day off in between," Nationals Manager Dusty Baker said. "I don't know if it was a letdown or [Braves starter Julio] Teheran. He was sharp. . . . Gio wasn't sharp tonight."

Gonzalez allowed five runs in five innings in what might have been his worst outing of the season — though he has not provided much to compare it to in that category.

As he recorded strikeouts for the first six outs, but also saw his pitch count climb toward 70 through three innings, Gonzalez displayed the Jekyll and Hyde extremes that have wrestled to define him throughout his Nationals tenure. When he is in control, he is an elite starter. When he is not, Gonzalez can be hard to watch, hard to pin down and hard to predict.

Gonzalez entered Tuesday with the third-lowest ERA among qualified starters — behind only Clayton Kershaw and Max Scherzer. Gonzalez will make $12 million in 2018, which is less than half of either of them.

The left-hander's résumé doesn't place him in the same elite tier as those Cy Young Award winners, but if there is a tier just below them, he probably fits there. Since Gonzalez joined the Nationals in 2012, he is tied for 14th among all major league starters in wins above replacement, 14th in strikeouts and in the top 20 in innings pitched.

The left-handers who rank ahead of him in most of those categories are Kershaw, Chris Sale, David Price, Madison Bumgarner, Jon Lester and Cole Hamels. Of that group, only Sale and Bumgarner have deals with a lower average annual value than Gonzalez's.

Gonzalez will be 32 years old next season, and at that age he will be exactly what he was for these Nationals at age 31 — a bargain. Perhaps he will not match the numbers he compiled this season, when everything seemed to go right and he seemed to subdue his demons with shock collars activated by a few deep breaths. What Gonzalez provides in October could define his value most in the end.

Unfortunately for the Nationals, his season is trending away from the ultra-efficient tightrope walk that was his first few months. From May 25 to Aug. 31, Gonzalez bucked his usual pitch-count problems and lasted six innings or more in all but one start.

He lasted just five in his last outing, and after two innings (and six strikeouts) Tuesday, he had thrown 49 pitches. The Braves pummeled Gonzalez, and it was the second time in three starts he allowed five runs or more — and just the third time all season. So often this season, Gonzalez found ways to escape self-inflicted trouble. Entering Tuesday, he allowed 16 hits with runners in scoring position all season. Tuesday, he allowed five in five innings.

"It was weird to me. . . . You get the strikeouts and then all of the sudden the hits came in," Gonzalez said. "It was just one of those games. You take it for what it was, sweep it under the rug and get ready for tomorrow."

Gonzalez didn't get much help from his teammates Tuesday. They showed the effects of clinching the National League East title Sunday. Michael A. Taylor, defensive stalwart, made an error. Trea Turner, master of the bases, got picked off. The offense couldn't score against familiar right-hander Teheran.

"I don't think [a letdown] was it. I just don't think we played very well today," catcher Matt Wieters said. ". . . We want to keep playing well. We want to keep winning. It's just our competitive nature."

Whether because of a letdown or some other reason, the Nationals played one of their most sluggish and uninspired games of the season — and that is just fine, because their playoff spot is now secure.

Such is the luxury provided by clinching, that an off-night like this will not cause concern. Such is the danger of clinching early, that guards go down and so does performance — just when it needs to peak. For the Nationals and their enigmatic left-hander, the key is now making sure one off-night does not spiral into many.