SAN FRANCISCO -- The sample is undeniably small, and the measure of a rotation is better left for September -- as the Padres learned last year. But, after one trip through their starting five, it’s hard to envision a better start to the season.

With a 4-2 victory over the Giants at Oracle Park on Monday night, the Padres are off to a 4-1 start -- one Opening Day bullpen implosion away from being perfect. Thus far, the San Diego rotation has combined to allow three runs on 11 hits across 27 innings.

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On Monday night, it was Nick Martinez’s turn. Making his Padres debut after four seasons in Japan, Martinez pitched five excellent innings, striking out six and working his way out of trouble on multiple occasions. The Padres would certainly be happy with a summer’s worth of those results out of the purported No. 5 spot in their starting rotation.

“We’ve got a great group of guys here that want to win, want to compete,” Martinez said. “I just want to pass the baton back to the next guy. I think we’re going to have a lot of healthy competition among the starters this year.”

It began Thursday with six no-hit frames from Yu Darvish, who was actually one-upped the following day when Sean Manaea didn’t allow a hit across seven. Joe Musgrove and Martinez were both solid in their outings as well, and Nabil Crismatt, making a spot start for Blake Snell, pitched three scoreless.

The Padres are hopeful they’ll get positive injury news regarding Snell on Tuesday when he plays catch for the first time since being scratched on Sunday with adductor tightness. Mike Clevinger is slated to begin a rehab outing later this week, as well. And, oh yeah, MacKenzie Gore, the team’s top pitching prospect, is coming off an excellent spring and just pitched five scoreless innings at Triple-A El Paso.

“We have a ton of potential,” said Padres catcher Austin Nola, who launched a go-ahead fifth-inning homer on Monday night. “So, yeah, we’re looking up.”

When Martinez arrived at Padres camp, Nola hadn’t seen much of his new batterymate. Before Nola ever caught Martinez, he faced him in a live batting practice session on Martinez’s very first day as a Padre. Martinez threw Nola all four of his pitches, striking him out on a changeup.

“I was like, ‘Wow, this guy is really good,” Nola said.

Martinez’s numbers in Japan last season back that assertion. He posted a 1.60 ERA in 21 starts for the Fukuoka Softbank Hawks. With the Padres in need of rotation depth, he was an obvious target. Martinez agreed to a contract on Dec. 1, in the hours before the lockout began, but it wasn’t finalized until March.

Then, the Padres threw Martinez into the fire during Spring Training. Every one of his starts came against a fully loaded big league lineup -- including an impressive spring debut against the Dodgers. With a 3.00 spring ERA against legit Major League competition, Martinez earned his spot in the Padres’ rotation -- and thus, his first start in the big leagues since 2017 with Texas.

“It was exciting to be back, for sure,” Martinez said. “I definitely had the juices flowing and the blood pumping.”

With Martinez entrenched in a starting role, the Padres were suddenly overflowing with starting pitching options after making a deal for Manaea five days before the season. That level of depth made Chris Paddack expendable. On Opening Day, San Diego used Paddack in a deal with Minnesota to land closer Taylor Rogers, who is now 3-for-3 in save opportunities this season after he nailed down another on Monday night -- and saddled his twin brother with the loss.

The innings between Martinez and Rogers got a bit nervy for the Padres. Steven Wilson allowed the tying run to score in the sixth on a wild pitch. Then, after the Padres took another lead on Manny Machado’s RBI groundout, left fielder Jurickson Profar made a brilliant sliding catch to prevent a run in the seventh.

“He saved my butt,” said right-hander Craig Stammen.

In the eighth, right-hander Pierce Johnson escaped a bases-loaded jam, before the Padres tacked on an insurance run in the ninth. Needless to say, the San Diego bullpen -- utterly spent at the end of the 2021 season -- can appreciate the efforts of its starting pitchers.

“We can come in and be fresh, and we can use all of our guys accordingly,” Stammen said. “It just sets up our whole pitching staff in general. Those guys have done a great job, first time through the rotation.”