ATLANTA -- Sunday afternoon’s 5-4 Marlins victory over the reigning World Series champion Braves concluded a season-opening stretch of 15 straight games against legitimate playoff contenders. It also marked just the second series win for Miami (7-8) at Truist Park since it opened in 2017.

Here are three questions that may have some early answers.

Who's the real Jesús Luzardo?
Two of his three starts have been good ones. After striking out a career-high 12 batters in Anaheim in his first start of the season, Luzardo ran into trouble against the Cardinals (4 ER in 4 1/3 IP). He bounced back in Sunday's rubber match, allowing two hits across five innings. Luzardo was cruising until walking three batters in the fifth, but he limited the damage to one run by retiring Austin Riley on high heat.

The 24-year-old southpaw has frontline stuff despite lining up as Miami’s fifth starter. His average fastball velocity (97.4 mph) ranks third fastest in the Majors. His slurve is a premium pitch, with opponents batting just 3-for-27 with 17 strikeouts against it this season. He recorded five of his eight strikeouts on the slurve on Sunday, though both of Riley's doubles came on it.

In large part due to Luzardo, Miami's rotation ranked as the following entering Sunday:

• Second in average fastball velocity (94.5 mph)

• Fourth in whiff rate (29%)

“I had a good one today,” Luzardo said. “I feel like there were good parts of it, bad parts of it. I'm not always going to be 100 percent, have my best stuff, so when I'm able to get out there and keep us in the game as long as possible, I'm happy to do that. I'm happy the way I'm starting the season, and hope to keep it rolling.”

Are the bats heating up?
Miami expected more offense with the additions of Jorge Soler (World Series MVP) and Avisaíl García (.820 OPS in 2021) via free agency and infielder Joey Wendle by trade. Healthy Garrett Cooper, Jesús Aguilar and Brian Anderson would provide length to the lineup. But that hadn't been the case through the first two weeks.

The Marlins entered the finale with the highest whiff rate (29.5%), second-highest ground-ball rate (48.8%) and the fourth-lowest average (.193) with runners in scoring position. Those bad trends appear to be coming to a close, at least for now.

Both García and Cooper picked up their first hits with RISP during Saturday's victory. That continued into Sunday, as they collected two-out RBI hits in the go-ahead two-run fifth. Cooper tacked on an insurance run in the seventh.

Manager Don Mattingly and bench coach James Rowson never expressed concern with the slow starts, because those players have proven track records. Soler, who reached base seven times in his return to Atlanta, admitted he has always been a slow starter.

“I think baseball, there's so many ups and downs that you try to do so much early on in the year that you kind of lose yourself,” said Cooper, who hit .328 with RISP in 2021. “You're just trying to be someone you're not. Just coming in and working on timing yesterday early, just to get everything rolling and seeing pitches. To be put in that spot, that's what I like to do, that's what I strive to do. I think not trying to overdo things definitely helped the last few days.”

How deep is the bullpen?
With several high-leverage relievers unavailable, Mattingly turned to right-hander Louis Head to record the final two outs of the game with three runs already across. Primarily a middle reliever, Head allowed a two-strike double to Marcell Ozuna before striking out Adam Duvall and Eddie Rosario for his first career save. The night before, Tanner Scott had collected his second career save. Both Head and Scott were offseason acquisitions.

Miami entered 2022 without an established ninth-inning arm, and the initial plan was to go closer-by-committee and work matchups. But Anthony Bender (hip soreness) has been the guy so far, going 2-for-3 in opportunities, with Dylan Floro, who tied for the Marlins team lead with 15 saves last season, on a rehab assignment. Despite lacking marquee names, the bullpen ranks 16th with a 3.33 ERA.

“We're just trying to put our guys in good positions,” Mattingly said. “We're going to have to get outs from all over the place. … We're going to need all our guys.”