SEATTLE — It felt like Dallas Keuchel barely worked a sweat.

At least compared to James Paxton.

And this Mariners’ defense for that matter.

The Mariners were hacking early, which kept Keuchel’s pitch count low. But manager Scott Servais has stressed the importance of attacking top-notch starting pitchers early and not allowing them to settle in.

They got just enough offense to go with some big pitching and defensive play for a 2-1 victory in the Mariners’ first meeting with the Houston Astros this season — handing the reigning World Series champions their fifth loss in their past six games.

It was Paxton’s first win and it came in the battle of elite left-handers.

“He knows he is very talented, but it’s got to be more than talent,” Servais said. “You got to go out and compete and you got to make adjustments. You start to see the emotions come out late in the game from him and that’s a good thing. I’ve always been a big fan of that when Paxton slams the glove after a big strike out.

“Nice to get him his first win. Hopefully he can guild off of that.”

Paxton, Nick Vincent, Juan Nicasio and Edwin Diaz combined to get 27 outs without allowing a run after the Astros’ George Springer did what he frequently seems to do in Seattle — lead off with a home run.

So make that five wins in their past six games for the Mariners.

And thank that in part to the Mariners’ defense. And three big plays in particular.

There was Mitch Haniger’s leaping catch at the wall in right field on reigning American League MVP Jose Altuve’s hard-hit shot with a runner on base. That ended the third inning.

Then Kyle Seager’s bare-hand, on-the-run throw-out of Marwin Gonzales at first base with Yuli Gurriel at second to end the fourth inning. The call stood after a replay review.

And then Haniger, again. This time with Paxton surpassing 100 pitches in the sixth inning. He robbed Gurriel of sure-extra bases when he covered seemingly all of right field and used every bit of his wing span to stretch and snatch the ball for the fly out.

Paxton pointed in recognition and then retired Evan Gattis to get out of the sixth after a season-high 106 pitches.

“That was huge. Haniger was great out there tonight,” Paxton said. “Jumping up on the wall, running down that ball out there — he’s been great and guys have been playing good defense behind me.”

“That’s about as far as you can reach to grab it,” Servais laughed. “I’m glad he’s got a glove as big as it is. We needed every inch of it.”

Meanwhile, Keuchel needed just 96 pitches in eight innings.

And the Mariners (9-5) had nothing but Taylor Motter’s single until Nelson Cruz happened.

Playing in his third game since returning from the 10-day disabled list, Cruz launched a laser-shot over the left-field wall on a 2-2 count for his third home run (in five total games) to tie it up.

Then the bottom of the sixth.

David Freitas has been known more for his defensive than offensive prowess as a catcher. But he continues to produce since he was recalled from Triple-A Tacoma when Mike Zunino headed to the 10-day disabled list.

Freitas led off with a double in the seventh inning. And Dee Gordon followed with a blooper into right field.

Springer slipped on his way to it and that allowed Freitas enough time to score and Gordon to end up at second with a double.

“George slipped, I slipped in the first (inning) — hopefully it gets better,” Gordon said.

And there were still no outs, with the rest of the top of the Mariners’ order to come.

But Jean Segura grounded out, Robinson Cano struck out, Nelson Cruz walked and Kyle Seager struck out to strand Gordon.

The Mariners had another chance with a runner in scoring position in the seventh after Guillermo Heredia’s one-out double. He then reached third on Taylor Motter’s ensuing single, but Freitas struck out and Gordon grounded out.

That looked to be enough, though, with Vincent and Nicasio shutting the Astros down to get six consecutive outs, setting the table for Diaz.

Diaz walked Carlos Correa to lead off the inning but then struck out pinch-hitter Josh Reddick and then Marwin Gonzales (on five consecutive sliders) to pick up his seventh save.

“Eddy had good stuff tonight,” Servais said. “He’s on a nice roll and it’s nice to see him out there often. That means we’re in a good spot.”

Indeed they are. With the Astros’ losing skid and the Mariners’ run, Seattle (9-5) just passed Houston (10-7) by a half-game in the AL West standings. The Angels sit in first place at 13-3.