ATLANTA -- The blazing four-seam fastball ticked up a notch for Tayron Guerrero in the Marlins’ 4-0 loss to the Braves on Friday night. In all, 11 pitches touched at least 100 mph, and the rangy right-hander sprinkled in a slider or two to keep hitters honest.

What the scoreless eighth inning showed is the tantalizing upside Guerrero possesses, raising questions again about whether the 28-year-old could eventually work his way into a closer role.

“That’s what I’m working for,” Guerrero said.

The Colombian native said he spent the offseason working on his secondary pitches to go with his upper 90 mph fastball.

“In the offseason I was working on my fastball and know, if I add another breaking ball -- a slider or two-seam -- I could be a closer,” Guerrero said.

The Marlins currently are going with matchups in save situations. The three primary candidates are Drew Steckenrider, Sergio Romo and left-hander Adam Conley.

All three bring something to the table, but Guerrero offers one thing the trio doesn’t -- the ability to reach triple digits with his fastball.

Guerrero entered Friday having touched 100 mph just once in his first three appearances. In the series opener with the Braves, he topped at 101.7 mph, and had a stretch of seven straight pitches at 100 mph or higher.

“I think there were sections of time last year where his stuff was just like that,” manager Don Mattingly said. “He is using his slider more. His slider has gotten better. We think that’s going to be a key for him to have that, to keep guys off his fastball. Because as the season gets going, guys are going to get on his fastball.”

For the season, Guerrero’s four-seam fastball average is 98.5 mph, and his slider averages 87.8 mph, according to Statcast.

With a power fastball like he has, Guerrero has thrown his four-seamer 73.2 percent of the time, and his slider 25 percent.

To become a closer, Guerrero knows his slider will have to be a pitch that hitters have to at least think about.

“That pitch is coming along very well,” Guerrero said. “It’s getting better every day. I focus on that every day and keep working on that. That’s going to make my fastball look even better.”

Guerrero worked back-to-back nights, working the fifth inning in relief of Sandy Alcantara in Saturday's 4-2 win over the Braves. He had to battle out of trouble, after walking Ronald Acuna Jr., and hitting Tyler Flowers with a 98.4 mph fastball. But he fanned Nick Markakis and didn't allow a run.

Worth noting

• Monte Harrison, the Marlins’ No. 2 ranked prospect, per MLB Pipeline, is missing the first few games at Triple-A New Orleans due to a sore right wrist. The 23-year-old outfielder is not expected to go on the injured list, but is likely to face live pitching in practice to test the wrist before he gets into the lineup.

• Right field is a position the Marlins likely will address most of the season. Peter O’Brien, a streaky hitter with huge power potential, is getting his opportunity in right. Garrett Cooper was the Opening Day right fielder, but he suffered a left calf strain in the second game and is on the injured list. At New Orleans, Austin Dean started in right field on Saturday, and he is a callup option if O’Brien continues to struggle.

• To help monitor innings, Class A Advanced Jupiter and Double-A Jacksonville will be going with six-man rotations. The Hammerheads have a talented young staff, with Trevor Rogers, Edward Cabrera, Braxton Garrett, Jordan Holloway and Will Stewart. Either Taylor Braley or Daniel Castano will also mix into the rotation. And at Jacksonville, the rotation will go to six when top prospect, Sixto Sanchez, is added to the roster. Sanchez, acquired from the Phillies in the J.T. Realmuto trade, is building up at extended spring training in Jupiter, Fla.