MIAMI -- Phillies right-hander Zach Eflin became a big-time pitching prospect because he threw an impressive two-seam fastball. His sinker is a big reason why the Phillies wanted him in the Jimmy Rollins trade with the Dodgers in Dec. 2014.

But Eflin essentially stopped throwing the pitch last season because the Phillies wanted more four-seam fastballs at the top of the strike zone. They wanted more swing and miss. The plan proved effective on multiple occasions, but pitchers need conviction behind every pitch they throw, so after returning to the rotation last weekend following a demotion to the bullpen in July, Eflin is throwing his sinker again. It proved remarkably effective Saturday night in a 9-3 victory over the Marlins at Marlins Park.

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“It had been three or four weeks in the making,” Eflin said. “Going back to the rotation, I was pretty dead set on doing it.”

Eflin allowed two runs in six innings. He induced 10 groundouts. He threw just 79 pitches, including 37 sinkers. It was his highest percentage of sinkers (46.8 percent) in a start since May 23, 2017 (58.8 percent).

“If Zach Eflin is getting the ball on the ground, something good is happening,” Phillies manager Gabe Kapler said. “So obviously swings and misses are nice and there are going to be times for those and right now he’s focusing on weak contact, efficiency and getting the ball on the ground and being successful with that approach.”

Eflin threw his sinker 29.8 percent of the time from 2016-17. It dropped to 12.9 percent from 2018 through July 27, when he made his final start before the demotion to the bullpen. He has thrown his sinker 39.4 percent of the time in his last two starts.

“It definitely feels a lot more comfortable,” he said. “There’s always a time for swing and miss and four-seams and whatnot, but fortunately for me I’ve always had a really good sinker.”

Eflin said he started to think about returning to his former self in the starts just before his demotion to the bullpen.

“I was really wanting to go back to sinkerballing and kind of getting early contact,” Eflin said. “That’s when I got moved to the bullpen. It was kind of tough to figure out again what I wanted to do from the bullpen, whether I wanted to keep doing the swing-and-miss stuff or if I wanted to start implementing my sinker.”

He said he did not have to twist the arm of pitching coach Chris Young to return to what he considers his strength.

“He was all for it,” Eflin said. “We simply sat down and talked about it and I told him what I thought I was best at doing. At the end of the day, it’s a two-way street. They want what’s best for me as well.

“If I’m at my best going out there throwing sinkerballs and getting early contact and going really late in the game, then that’s what’s going to be best for the team. There was no point where they were against me saying anything about it.”

The throw-strikes-swing-early-pitch-deep philosophy has worked for countless pitchers in the past. Eflin believes it can work for him in the future, too.

“I have to do what I have to do to be the best version of me on the field,” Eflin said. “If that’s it, that’s what I’m going to do.”

Of course, it is just one start. The Marlins have the worst record in the National League, although they scored 19 runs against the Phillies on Friday. But the Phillies are searching for consistent, quality starting pitching from anybody not named Aaron Nola. It is a must if they expect to pass the Cubs for the second National League Wild Card spot. The Phillies will enter Sunday’s series finale in Miami just 1 1/2 games behind the Cubs.

At least the Phillies’ offense looks capable of providing their pitchers more consistent support. Since the Phillies named Charlie Manuel their hitting coach on Aug. 13, the Phillies’ offense has slashed .264/.356/.469 and averaged 6.3 runs per game in 10 games. They slashed .245/.322/.417 and averaged 4.7 runs per game beforehand. Corey Dickerson went 4-for-5 with two doubles and five RBIs on Saturday. Scott Kingery hit a three-run homer.

Kapler praised Rhys Hoskins, who went 0-for-3 with three walks and saw 42 pitches.

“He helped us win the game by getting on base and seeing pitches,” Kapler said.