SEATTLE -- When the Mariners installed Marco Gonzales as their No. 1 starter this spring, they couldn’t have asked for much more than what the 27-year-old delivered in a difficult season for the rebuilding club.

Gonzales wrapped up his 2019 campaign with seven innings of one-run ball on Saturday in a 1-0 loss to the A’s on a chilly evening at T-Mobile Park. Lack of run support left him on the losing end in his finale, but the former Gonzaga standout finished with a 16-13 record while setting career bests for wins, ERA (3.99), innings (203), strikeouts (147) and starts (34).

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On the heels of a 2-1 loss at Baltimore in his previous outing, Gonzales easily could have bumped his win total up to 18 with a little help his past two starts. But still, his value is clear when noting the Mariners went 17-17 in games he pitched, compared to 50-77 with anyone else on the mound.

Reaching 200 innings and staying healthy and strong for a full season were Gonzales’ primary goals after he totaled 166 2/3 frames -- and hitting the wall with a rough August -- last year in his first full season back from Tommy John surgery.

Gonzales is one of 14 MLB pitchers to have reached 200 innings this season and he's the first Seattle pitcher to achieve that mark since Félix Hernández in 2015.

“My main motive was just to go out and show my teammates and coaches and fans and the city just kind of what I’m made of, how I finish strong,” said Gonzales, who went 2-2 with a 1.61 ERA in 28 innings over his final four starts. “My plan is to have more starts after this some day, so I want to show everybody I’m capable of doing that.”

Gonzales is regarded by the Mariners as one of their mainstays going forward, a stabilizing force in what figures to be a young rotation that will add No. 9 prospect Justus Sheffield and likely Justin Dunn (No. 5) on a full-time basis next year.

“Very, very impressive,” Mariners manager Scott Servais said of Gonzales’ season. “It was a goal of his to make every start. There are starts you feel great and some you don’t, but you take the ball and go out there and that’s what the consistent ones do, over and over. He’s one of those guys. When you look back, he’s going to have a really nice career when this is all said and done if he stays healthy.”

Despite the team’s struggles this year, Gonzales has been buoyed by what he’s seen from the influx of youth late this season.

“I’m really optimistic,” he said. “I think the best thing about the young guys coming in is they’re absorbent to everything and love to learn. They’re humble and work hard. You give me those qualities, and I’ll go to war with anybody.”

The only damage done by the A’s on Saturday was a two-out homer by Ramon Laureano in the third inning, when Gonzales left a 3-2 sinker up in the zone and the A’s right fielder sent it over the wall in left with a 392-foot shot.

Gonzales threw a career-high 118 pitches while allowing five hits with three walks and four strikeouts, as Servais let him go as deep as possible while trying to pick up the victory.

“Marco was outstanding again,” Servais said. “Really, a great way to cap off his season. Unfortunately, we weren’t able to get him a ‘W.’ It was a well played game and it comes down to one swing and theirs went over the fence.”

The A’s improved to 97-64 and, with the win, clinched home-field advantage in Wednesday's American League Wild Card Game presented by Hankook Tire on ESPN. Seattle slipped to 67-94 heading into Sunday’s season finale.

The A’s were 19-25 on May 16 after being swept in a two-game series in Seattle, with the Mariners at 22-23. Since then, Oakland has an MLB-best record of 78-39, while Seattle went 45-71.

The Mariners have totaled just six runs while going 1-5 over their last six games and they managed only six hits on Saturday against Brett Anderson and three relievers.