The 4 main storylines that defined April for the Padres

This story was excerpted from AJ Cassavell’s Padres Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

SAN DIEGO -- The last time the Padres won 18 games in April, they went on to win 98 games and the National League pennant.

This was a wildly successful April in San Diego -- even if it ended with a pair of disappointing losses to the Cubs.

Here are the four storylines that defined the month -- and how they’ll impact the rest of the Padres’ season:

Stammen is learning on the fly -- and he has impressed
Craig Stammen has been on the job for over a month now. It hasn’t been perfect. But -- for a rookie manager without experience at any level -- it’s gone about as well as anyone could’ve reasonably expected.

We’ve learned a few things about Stammen’s tendencies: He wants to use his bench extensively. He’s committed to keeping his regulars fresh and giving them time off.

If there’s one place to find fault, it’s this: Stammen might trust his guys too much at times. If he makes a mistake, it’s going to be because he leaves his pitcher in the game a batter too long. Or because he sticks with his guy at the plate, rather than opting for a pinch-hitter.

Sometimes it works -- Nick Castellanos delivered the go-ahead single in an obvious pinch-hit spot on Monday. Sometimes it doesn’t -- Bryce Johnson struck out in just about the same situation a day later.

But the most important thing is this: Stammen is willing to adjust and adapt. He knows he’s new at this and that he’ll make mistakes -- and that those mistakes are to be learned from.

He’s doing that in real time.

Lingering starting-pitching questions
It’s been an eventful April for the rotation. Nick Pivetta went down with a flexor strain in his right elbow. Joe Musgrove’s progress has stalled. The Padres’ rotation needed a boost. So they signed the lone remaining impact starter -- Lucas Giolito.

Giolito will need a couple Minor League starts to build up, putting him on course for a mid-May debut. Meanwhile, Griffin Canning is on his way back as well. He pitched five innings of one-run ball at Triple-A El Paso on Tuesday.

There’s help on the way. Which is a good thing, because the back of the Padres’ rotation features some major questions.

I think those questions are going to define the first half of the season. The Padres’ bullpen is elite. Their offense features a deep lineup with a deep bench. The superstars will hit sooner or later.

If this roster has a World Series-caliber ceiling, the rotation feels like the one thing that might hold it back. The Padres need Pivetta and Musgrove healthy and dealing. But that’s no guarantee. Which is why these questions will persist -- perhaps right up until the Trade Deadline.

Tatis’ odd start
No one has seen anything like it. Everyone is convinced it’ll change.

And yet, it’s now May -- and Fernando Tatis Jr. still hasn’t homered.

No one in the Majors has a better hard-hit rate than Tatis’ 66.7% mark. But he’s also not hitting the ball in the air nearly enough. And when he does, he’s not hitting it pull-side, where it’s significantly easier to hit the ball out of the park.

“Small tweaks and hopefully some good luck, and go from there,” Tatis said.

Even without the requisite launch angle to hit homers, Tatis is still getting wildly unlucky considering the contact he’s making. He’s been scorching baseballs right at defenders. His .413 expected slugging percentage is 129 points higher than his actual mark -- one of the largest gaps in the game.

On Wednesday, after a deep drive to center with the bases loaded, Tatis was asked if he felt close.

“I’ve been close for a while,” he said. “But it’s just a sacrifice fly.”

On to the next streak
Let’s be clear: Mason MillerMason Miller’s scoreless streak did not end because of a bad call. Miller’s scoreless streak ended because, after a bad call, he allowed two hits and a wild pitch. It’s part of Miller’s job to deal with the bad calls as they come. (And, to be clear, he did that! He dealt with the call and closed the door on a victory.)

“Padres win,” Miller said afterward. “That’s what matters.”

Enough about the call already. This was a streak that dates back to August. In any 34-game stretch, you’re going to have breaks go for and against you. You deal with them -- the good and the bad.

This isn’t just me speaking. It’s what Miller believes, too. I asked him about it -- and the fact that somewhere along the way, he might’ve benefited from a call or two. He pointed out that the very first pitch of that Matt Shaw at-bat was well outside -- and called strike one.

Miller is both remarkably humble and fiercely competitive. What irked him most about Monday wasn’t a bad call. It was the hittable pitches he threw.

What impresses me most about Miller -- maybe more than the 103-mph fastballs and the filthy putaway sliders -- is his ability to self-evaluate. Even during his franchise-record streak, he was rarely content. He wants to get better. And in order to get better, Miller needs to be honest with himself about the mistakes he makes. (Even if he usually gets away with them, because his stuff is just that overpowering.)

That mindset, as much as anything else, is why I’m convinced Miller started a new scoreless streak on Wednesday.