SAN FRANCISCO -- When the big leagues came calling for Chris Paddack this spring, he practically kicked down the door.

The brazen right-hander wore a black suit with a pink tie and a cowboy hat to his March debut against the Giants. He burst onto the scene with a high-octane fastball and a swing-and-miss changeup. Paddack talked a big game, and then he backed it up. It all seemed so easy.

Then, suddenly, it wasn't. For the first time in his life, Paddack was hittable. Entering play Thursday night, Paddack’s ERA had ballooned by a full run during the second half.

He wasn't about to let his rookie season end like that.

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Coming off the worst start of his professional career last Friday against the Red Sox, Paddack responded in style. He pitched the Padres to a series-opening, 5-3 victory over the Giants at Oracle Park on Thursday night. Over seven innings of one-run ball, Paddack struck out eight and didn’t allow a walk.

“Got back to myself,” Paddack said. “That was the biggest thing.”

The 6-foot-4 right-hander retired 10 straight Giants hitters to open the game. When he grooved a changeup that Brandon Belt launched into McCovey Cove, he didn’t flinch, bouncing back with three more scoreless frames.

“That's what you want to see,” said Padres manager Andy Green, “a guy working to get better and not being accepting of a couple bad outings.”

Right now, it's unclear how much longer Paddack's impressive rookie season might last. He pitched only 90 innings in the Minors last season as he returned from Tommy John surgery.

The Padres have meticulously mapped out Paddack’s debut season. They’ve spaced at least five days between all of his starts this season, and they even sent him to the Minors for 10 days of rest in mid-June. The club won't disclose an innings limit, but Paddack has already eclipsed his 2018 total by 34 1/3 frames.

“I know here soon I’ll probably be getting some news that I don’t want,” Paddack said. “But they haven’t told me yet. So I’m looking forward to my next start.

“Obviously, if I could pitch every day I would. The reality is: They have standards and rules that they told me at the beginning of the year they were going to hold to. Whenever that time comes, I’ll accept it and get ready for the next season.”

Paddack’s second-half struggles led many to wonder whether fatigue was playing its part. But he certainly looked fresh on Thursday. Paddack attacked the zone from the outset, throwing 67 of his 92 pitches for strikes and inducing 15 swinging strikes. His fastball had the same life it did in April.

He got plenty of early support, too. Manuel Margot launched a two-run homer in the third, and Austin Hedges did the same in the fourth, helping the Padres build a 5-0 lead. The Giants rallied to bring the tying run to the plate in both the eighth and ninth innings. But Matt Strahm and Andres Munoz worked out of their self-induced jams. In the process, the 20-year-old Munoz became the youngest pitcher in franchise history to record a save.

It was a gutty effort from two Padres relievers who had also pitched during Wednesday’s bullpen day against Los Angeles. San Diego used eight bullpen arms, and a number of them -- including closer Kirby Yates -- were unavailable on Thursday night.

“There were a lot of guys who were tired today and a couple who were able to take the baseball,” Green said. “They got the job done. … It takes a little while to rebound from the type of game we had [Wednesday].”

The Padres seemed determined to make sure one loss wouldn’t spiral into two -- even though their 6-4 loss to the Dodgers on Wednesday threw a serious wrench into their travel plans. The extra-innings defeat caused the Friars to miss curfew at San Diego International Airport. They instead flew north on gameday and didn’t land in the Bay Area until early Thursday afternoon.

After the game, Paddack had a confession to make.

“I'd be lying if I didn't tell you this,” he said. “Last night, I was pretty frustrated. I was like: This is going to throw me off a little bit. But today I accepted it, moved on, and I was like, ‘I'm not going to let this ruin a good outing.’”

It didn’t. Once again, Paddack was the dominant version of himself on Thursday night, seemingly determined to end his rookie season the way he started it.