Who has the ninth? As Seranthony Domínguez dominates, Phillies also remain confident in Zach Eflin.

ATLANTA — Zach Eflin punctuated the Phillies’ first three playoff games — victories all — by recording the last out. But he allowed a run in Game 1 of the wild-card series in St. Louis, put the tying run on base in the clincher, and gave up a three-run homer in a too-close-for-comfort series-opening win over the Braves.

The most pressing question, then, entering Wednesday’s rain-delayed Game 2 — other than when the actual game would begin — was this: The next time the Phillies have a lead in the ninth inning, would they turn to Eflin again?

“He’s an end-of-the-game option, not necessarily the ninth inning,” manager Rob Thomson said before the Phillies lost, 3-0, in Game 3. “If his pocket [of the opposing lineup] shows up in the ninth, I still have full confidence in him.”

» READ MORE: Seranthony Domínguez backs up Phillies’ faith in him by striking out Cardinals stars in key spot

Thomson has run the bullpen based on matchups since he removed struggling Corey Knebel from the closer role in the middle of June. Rather than assigning a specific inning to each reliever, he deploys them based on the game situation. If the heart of the opposing order is due to bat in the seventh or eighth inning, he typically uses his highest-leverage reliever then and chooses someone else for the ninth.

But there’s just something different about the ninth inning, especially in the playoffs. Closing out a game requires what Thomson describes as “a slow heartbeat.” Lately, he has liked Eflin’s pulse rate, even though the right-hander is a converted starting pitcher who didn’t get his first save opportunity until Oct. 3.

Seranthony Domínguez is a cool customer, too — and a more traditional choice to pitch in the ninth inning, to boot. And after missing three weeks with elbow tendinitis and struggling with his mechanics (and, consequently, his command) late in the season, he has regained his dominant mojo in the playoffs.

Domínguez, the Phillies’ relief ace for most of the season, has faced nine batters and retired them all, five by strikeout. In Game 1 against the Braves, he mowed through the heart of the order on only 18 pitches. Three nights before that, on Saturday, he fanned St. Louis Cardinals sluggers Paul Goldschmidt and Nolan Arenado in the eighth inning of the wild-card clincher and had one thought as he walked off the mound.

“I’m back,” Domínguez said Wednesday. “I feel like I am.”

If that’s the case, could Domínguez be the choice to in the next ninth inning with the game on the line?

Thomson hasn’t named a closer since June. He isn’t about to start now. Generally speaking, he acknowledged that it can help to have a reliever with swing-and-miss stuff in the ninth inning. Domínguez, armed with a fastball that occasionally scrapes 100 mph, had a 29.5% strikeout rate this season. Eflin is a ground-ball pitcher.

» READ MORE: Zach Eflin’s playoff-clinching first save after a long road back to Phillies was ‘really special’ to his dad

“I think swing-and-miss [is preferred] for chase hitters and ground ball for contact hitters,” Thomson said. “The one thing that I think is mandatory is that you have to have a slow heartbeat and be able to control that moment. I think that’s a huge part of it.”

Thomson said Domínguez has looked more self-assured in the postseason than he was down the stretch.

“He looks different now,” Thomson said. “I think he was a little bit [tentative] when he first came back, and I think that’s a natural thing. This is a young kid with a bright future. But I’m seeing a guy that we know and we’ve seen the last few years come out this time of year.”

» READ MORE: ‘I never expected to throw 100′: Inside the reemergence of the Phillies’ Seranthony Domínguez

Late in the season, Domínguez said he believed his arm may have been “a little late” in relation to the rest of his body as he delivered the ball. He worked with pitching coach Caleb Cotham, bullpen coach Dave Lundquist, and director of pitching Brian Kaplan to correct the problem.

“When I make my delivery to the plate, I feel like my upper body was going forward a little bit,” Domínguez said. “Right now, I’ve been working and watching video and trying to find the way to get back to the point where I was before. And right now, I feel really confident, and I feel like my body is on track.”

Kyle Schwarber went 0-for-4 with three strikeouts in Game 3, deepening his postseason skid to 0-for-16 with eight strikeouts. But the Phillies aren’t mulling any changes in the leadoff spot.

“I’ve given no thought to it because that’s who Schwarb is,” Thomson said before Game 2. “He goes through some down times. But when they’re good times and he’s hot, he’s as hot as anybody. So we’ll just wait it out.”

Said Schwarber: “I’m the guy at the top of the lineup. I have to be able to get on base and start things for these guys. I don’t feel bad or anything up at the plate. I just have to be able to make the adjustments and go from there.”

» READ MORE: How the Phillies’ Alec Bohm learned to overcome the ‘valleys’ to prove he belongs

Both teams made slight alterations to their lineup for Game 2 based on pitching matchups. Lefty-hitting Brandon Marsh and Bryson Stott were back in the Phillies’ lineup over Matt Vierling and Edmundo Sosa, respectively, against a right-hander (Kyle Wright). The Braves went with Marcell Ozuna and Eddie Rosario over William Contreras and Robbie Grossman, respectively, against Zack Wheeler. ... The Braves didn’t name a Game 3 starter, although Charlie Morton and Spencer Strider are the likeliest possibilities. The Phillies will counter with Aaron Nola.