SAN DIEGO -- Grayson Rodriguez is having the best summer of his baseball life. He’s pitching for the best team in the American League in the midst of a pennant race. He has thrown more innings than in any previous season of his professional career. And the 23-year-old right-hander is doing it for an Orioles team filled with youth in a fun, lighthearted clubhouse.

One aspect has been similar to previous years for Rodriguez, though. As the heat and humidity levels rise -- a feeling he’s quite used to as a native of Nacogdoches, Texas -- so have the radar-gun readings for his fastball. That’s one of the biggest reasons why Rodriguez has turned a corner in his rookie season, leading to his best outing yet Monday night at Petco Park.

While routinely throwing his heater 99-101 mph, Rodriguez carved through San Diego’s star-studded lineup, tossing a career-high seven innings of one-run ball and leading Baltimore to a 4-1 series-opening victory. He scattered three hits, walked one and struck out six.

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The Orioles (74-45) improved to a season-high 29 games above .500. Ryan O'Hearn homered and Gunnar Henderson hit a three-run double to account for the offense against Yu Darvish.

But it was Rodriguez’s electric stuff that again stole the show.

How exactly is Rodriguez throwing so hard, despite already having logged a career-high 122 1/3 innings (between the Majors and Minors)?

“Just the summertime, I guess,” Rodriguez said with a grin. “Ever since 2019, in Low-A [Delmarva] to [Double-A] Bowie to everywhere else, I think August has been my best month for velo. So we’re going to keep that going, and, hopefully, we’re going to carry that into September and when October gets here.”

Rodriguez is proving that as long as he stays fresh, he could make an impact in October, should Baltimore get to the postseason for the first time since 2016.

In his initial 10-start stretch in the big leagues across April and May, Rodriguez couldn’t pitch deep into games and consistently struggled with command. Since returning to the Orioles on July 17, he has shown why he was one of the best pitching prospects to come through the organization in years.

First 10 starts: 45 1/3 innings, 7.35 ERA, 56 strikeouts, 21 walks, .307 average against.
Past six starts: 35 2/3 innings, 3.03 ERA, 30 strikeouts, 11 walks, .195 average against.

“I feel more kind of like myself,” Rodriguez said. “That first stint in the big leagues, I don’t like to say that was me.”

Added manager Brandon Hyde: “Just such a huge difference from when he came back -- an amazing job of deliveries, a better tempo of the delivery. The command is better with his fastball. He’s pitching with way more confidence.”

Rodriguez touched 101 mph for only the second time in the big leagues on his fifth pitch of Monday night, when he got Ha-Seong Kim to ground out back to the mound. He threw 22 fastballs at 99 mph or higher.

Of Rodriguez’s 95 pitches, 38 were four-seamers. His heater averaged 98.9 mph (1.7 above his season average), per Statcast, and it induced seven whiffs. He again relied heavily on his slider, as well, which he threw 32 times (five of which resulted in whiffs).

“Unbelievable. Electric stuff, obviously,” O’Hearn said. “From my angle, it’s cool to see just how effortless it looks. But he was mixing it up, throwing strikes with all his pitches, attacking guys.”

Rodriguez pitched into the seventh for only the second time as a big leaguer. He previously went 6 1/3 scoreless innings in a win over the Yankees on July 28.

The lone damage the Padres did against Rodriguez was a sixth-inning leadoff homer by Garrett Cooper that traveled a Statcast-projected 439 feet to straight-away center field. It was the first time Rodriguez gave up a homer in his six starts since rejoining the Orioles’ rotation.

San Diego’s hitters could tell from Rodriguez’s arsenal it would be a challenging assignment.

“First of all, he's throwing 100,” Padres right fielder Fernando Tatis Jr. said. “But after that, for me, it was the difference between the slider and the [curveball]. He executed well.”

The rest of Baltimore’s roster is enjoying watching the maturation process of one of its young future stars.

Meanwhile, Rodriguez is enjoying the support he’s getting each time he takes the mound during this incredible season for the O’s.

“Obviously, the defense stands out -- one of the better defending teams in the big leagues,” Rodriguez said. “So that just makes a pitcher’s job really easy. And especially when you’ve got those guys in that lineup stacked up and they’re scoring you some runs. It’s a lot of fun.”