PHOENIX -- On Sept. 30, 2018, the Mariners closed out their season by notching their 89th win. It wasn’t enough to lead Seattle to its first postseason appearance since ‘01 -- a drought still active to this day -- but it marked the most successful team that Kyle Seager had been a part of in his big league career.

Perhaps the 2021 Mariners are changing that.

• Box score

Seager swatted a pair of three-run homers in an 8-5 win over the D-backs on Saturday night at Chase Field, helping the Mariners improve to 74-62. It’s the first time Seattle has been at least 12 games above .500 since the end of the ’18 season, when it ended 16 games over.

Although the Mariners are still four games behind the Red Sox -- who have won four straight -- for the second American League Wild Card berth, they’ve caught the A’s, who are now also four back of the Sox after losing to the Blue Jays each of the past two days.

Seattle has won four straight games and five of its past six, a stretch in which four contests have been decided by one run.

“It’s been awesome, our pitching’s truly been incredible. To win these one-run games, that’s what it boils down to, right?” Seager said. “Offensively, we’ve done just enough, but our pitching … that’s certainly been the key. We play good defense and we’re pitching really well. That’s definitely been our brand.”

As for Seager’s brand in 2021, it’s been increased power. He had never previously hit more than 30 homers in a season, and he had only reached that number once (2016). This year, he has 33 homers in 134 games.

On Saturday, Seager’s first three-run blast came before an out was recorded. After J.P. Crawford and Mitch Haniger opened the night with back-to-back singles, Seager belted a 399-foot homer to right off D-backs starter Humberto Castellanos.

Arizona answered with four runs in the bottom of the first, and the two teams went back and forth until the game was tied at 5 in the sixth. That’s when Seager came through with his second homer -- a two-out, 406-foot shot off left-hander Caleb Smith that landed in the pool in right-center field and gave Seattle an 8-5 lead.

“The longer you play, you have an idea of the pitches you’re looking for and what you can do with them,” Mariners manager Scott Servais said. “Kyle’s always been very good at pulling the ball in the air. That’s how you hit home runs in this league. Not many guys can go opposite field and live out there for their career, you’ve got to pull the ball in the air. Kyle’s looking for certain pitches, and his swing’s been in a good spot the majority of the year.”

Seager became the first Mariners player to hit a pair of three-run homers in the same game since Daniel Vogelbach did it on July 19, 2019, against the Angels.

In a Seattle lineup with plenty of youth, Seager provides a consistent presence in the middle. And his teammates greatly appreciate the big hits that the 33-year-old third baseman continues to deliver in his 11th big league season.

“A lot of them come in such clutch situations, too, to put us on top or to get us right back into the game,” said Crawford, who went 4-for-5. “The guy’s a true professional, man. He just gets it.”

Added Seattle starter Marco Gonzales: “I hope he plays for 10 more years, because he’s putting on quite a show right now.”

If the Mariners can keep rolling and push their way up the Wild Card standings over the final 26 games of the season, maybe Seager will get to experience the postseason for the first time.

Regardless of whether Seattle ends up there, it can count on Seager to do his part to try to make it happen.

“Something I’ve taken very seriously over the years is my job is to go out there and play wherever [Servais] tells me to and hit wherever he tells me to,” Seager said. “And then you just go out there and you try to do your job every day. That’s something I’ve certainly been proud of.”