SAN DIEGO -- When Brandon Maurer has struggled in his three seasons since joining the Padres, it's often attributable to his slider. When he's had success, it's generally for the same reason.

Maurer's slider is undoubtedly his make-or-break pitch, and over the past three weeks it's been filthy. Needless to say, success has followed.

Maurer's ERA balooned to 6.53 on June 25. In seven outings since, he's allowed just three baserunners -- all singles -- over seven scoreless innings, while striking out eight. He breezed through a perfect ninth Saturday, before Hector Sanchez walked off the Giants for a 5-3 win. In essence, Maurer has earned his way back into the ninth-inning role, and he could be pitching himself into a very serviceable trade chip.

The biggest difference? An uptick in Maurer's average slider velocity.

April: 83.1 mph

May: 83.8 mph

June: 82.9 mph

July: 87.0 mph

"I've wanted to get back to that for a long time," Maurer said of his upper-80s slider. "That's how it was in Seattle, then I came over here and started throwing the curveball, and they kind of morphed. I guess all it took was a little mindset change there."

It wasn't rocket science that Maurer needed to throw more hard sliders.

He's thrown 36 sliders this season at 85 mph or harder. Among those, he hasn't allowed a hit, and he's gotten 11 swings and misses.

On the flip side, he's thrown 113 sliders below 85 mph. Opponents are hitting .423 against them with just 10 swings and misses.

"When he's throwing his pitches pretty much as hard as he can, that's when he's at his best," said Padres catcher Austin Hedges . "He's one of the few guys that have great control while literally being max effort."

So what, exactly, did Maurer change to add to his velocity? Physically, nothing at all, he says. He's merely begun thinking of the pitch as a cut fastball in the moment before he throws it.

"Mindset-wise, I'm throwing cut fastball instead of slider," Maurer said. "I guess as long as you're thinking fastball, you're staying on top of the ball a little longer, the ball comes out a little harder."

The difference is palpable.

"I remember the slider he had in 2015 was really good, and he was able to throw it to both sides of the plate," said Hedges. "This year it's been a little bit bigger, and I don't think he was able to throw it for a strike as much. It was more of a chase pitch. The tighter it gets, he can throw it for both a strike and for a chase, which is huge."

AJ Cassavell covers the Padres for MLB.com. Follow him on Twitter @ajcassavell.