PHOENIX -- Chris Paddack wanted to stay healthy in 2019. He wanted to be reliable. He wanted to keep improving. And the Padres' right-hander continues to do that into September, a month that he had never previously pitched into during his professional career.

He may not pitch for much longer. At any point now, the Padres may decide Paddack, well above his previous career high innings mark, is done for this season. But until then, the rookie will continue to pitch -- and pitch well, if Wednesday night was any indication.

Paddack delivered another strong outing as he tossed 5 1/3 scoreless innings in San Diego’s 4-1 loss to Arizona in the series finale at Chase Field. After posting a 10.06 ERA in four starts from Aug. 4-23, Paddack has allowed only one run in 12 1/3 innings over his last two starts, striking out 16 and walking two.

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Could they have been Paddack’s final outings of the season? Perhaps, but he’s not focused on that.

“I can’t control that. If they give me the ball, I’ll be ready,” said Paddack, who has pitched 129 2/3 innings in 2019. “That’s kind of my mindset right now. I’m just excited and blessed to be pitching into September with being healthy. That was the biggest thing going into the year -- showing them I could pitch every sixth day and not miss a start. Showing them that I can get stronger as the innings go on, and I think I’ve been proving that to myself and the organization.”

The Padres continue to monitor Paddack’s workload after he underwent Tommy John surgery in 2016, missed all of ‘17 and pitched only 90 innings in the Minors last season.

When Paddack reaches 90 pitches, the club typically doesn’t let him face another batter. In the sixth, he gave up two straight singles to Ketel Marte and Eduardo Escobar, then struck out Christian Walker, which put Paddack at exactly 90 pitches. That’s when manager Andy Green came out to pull Paddack and put right-hander Craig Stammen into the game.

Stammen escaped the jam to preserve the scoreless outing for Paddack, who allowed four hits and struck out eight.

“I’m really pleased with his last couple of outings, and tonight was just a continuation of the last one,” Green said. “It starts with fastball command, and it was really good from the get-go. His misses, instead of kind of being beltline across, might just be off the plate or just a little bit down or a little bit up, so he’s not leaving it in the heart of the plate as much. And I think you can see that by the quality of the swings they’re taking against him.”

Paddack attributes some of his recent success to his changeup, which he threw 24 times. He induced six swinging strikes with the pitch, along with two called strikes and three fouls, and the D-backs had only one hit off the change, which was Escobar’s sixth-inning single.

When Paddack was struggling this year, he wasn’t as effective with the pitch. But he believes that he can now rely on the offspeed offering again.

“It’s there, it’s back,” Paddack said. “I’ve been focusing on that the past two weeks in my bullpens, focusing on my throwing program, just trying to focus on the little things. Tonight, I was very pleased.”

For the second straight night, San Diego couldn’t turn a solid outing from its starter into a win. With the game scoreless in the seventh, an inning after Paddack departed, Padres right-hander Luis Perdomo gave up a one-out grand slam to Marte, Arizona’s only offense of the game.

Meanwhile, D-backs right-hander Zac Gallen pitched seven dominant innings, allowing only one hit -- a one-out single by Manny Machado in the seventh. San Diego scored only two runs over its final two games in the desert as it was swept by Arizona in the three-game set.

“We didn’t have consistently good at-bats this whole series,” Green said. “We just didn’t mount much.”

But one positive takeaway for San Diego is how Paddack’s rookie season is finishing up, as he lowered his ERA to 3.54 through 24 starts and continued to pitch well despite the uncertainty of when he could be shut down.

“I’ve just been telling myself the past few weeks to pitch to my strengths, not to a hitter’s weakness,” Paddack said. “And I think that I like that mentality a lot going into the game.”