PHOENIX -- Brandon Pfaadt was at home in Kentucky over the All-Star break when his phone rang. The D-backs' right-hander checked the caller ID and saw that it was Arizona pitching coach Brent Strom on the other end.

Pfaadt wasn’t in the big leagues when Strom called him -- he had been optioned for the second time this season to Triple-A a little more than a week before -- but Strom, whose mind is always working, had an idea.

Strom told Pfaadt that he wanted him to shift from the far third-base side of the pitching rubber to the far first-base side because, he believed, it would make Pfaadt’s pitches more effective.

More importantly, though, Strom shared something else.

“He was, like, ‘Hey, we’re going to need you in big games in the postseason, later on in the season,’” Pfaadt said. “So that's kind of what the call was about, too, and giving that reassurance. It was good.”

It also proved to be prophetic. A couple of weeks later, the D-backs called Pfaadt up -- and with his new setup on the rubber, he began to find the success that had eluded him in his previous two big league stints.

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With injuries having decimated the Arizona rotation, coupled with the struggles of some veteran arms, Pfaadt has found himself an important part of the postseason rotation behind Zac Gallen and Merrill Kelly.

Pfaadt started Game 1 of the NL Wild Card Series against the Brewers and is slated to pitch Game 3 of the NL Division Series against the Dodgers on Tuesday night.

“To be able to slot him in the way we have, and just assume that he's going to go out there and execute, has been a great luxury for us,” D-backs manager Torey Lovullo said. “It's just nice to know that Brandon can execute, follow a game plan and make pitches.”

Things didn’t go great for Pfaadt in his first postseason start in Milwaukee when he allowed three runs in 2 2/3 innings, but the D-backs believed that the issues in that game were correctable with a different use of his pitches.

“I think if he sequences better, the stuff is there, I think he should have a better result tomorrow,” Lovullo said on Tuesday.

As he came up through the D-backs system, Pfaadt received rave reviews not just for his pure stuff or his results -- he led all of Minor League Baseball in strikeouts last year -- but also for his mental toughness.

He would need to rely on that toughness each time he got sent back to Triple-A Reno this year.

The first was when he didn't make the Opening Day roster, despite having an outstanding spring.

“I think I still knew that I could go down, take care of business and I’d be back,” Pfaadt said. “Anybody in that situation would be disappointed, but it was fine.”

When he first came up in early May, Pfaadt compiled an 8.37 ERA in his first five starts and was optioned back to Reno. It was new territory for Pfaadt, who to that point had only experienced tremendous success in his pro career.

“That was a little harder to deal with,” Pfaadt said. “I thought it would go better. I think there were two routes I could’ve gone after that, and I took the right one ... stayed positive and went down there and worked on the certain pitches they wanted me to work on, and then came back even stronger and determined to show everyone the real pitcher I can be.”

Pfaadt was called back up at the end of June, but that stint lasted just one start before he was sent back down.

It was not long after that when Strom called and Pfaadt changed where he stood on the rubber. Success finally came -- and Pfaadt now can see the value of those early struggles, and how they’ve made him into a better pitcher.

“I think it was a blessing in disguise for it to happen sooner than later,” Pfaadt said. “Everyone struggles at some point. If it were happening now, it would probably be worse than it happening during the regular season. I've learned a lot through it and gotten stronger.”