Braves rookie Sean Newcomb didn’t out-pitch Marlins starter Dan Straily, but he registered another quality start in his second major league outing Friday night.

Newcomb pitched six innings, allowing three runs in a 5-0 loss at SunTrust Park. Despite losing his first two starts, Newcomb owns a 2.19 ERA in 12 1/3 innings. The Braves scored one run in those games — none with him on the hill.

“I liked Newcomb, thought he did a really good job,” Braves manager Brian Snitker said. “The one inning he got in trouble, a couple of mis-hit balls to load the bases, and I really like how he went after (Marlins catcher J.T.) Realmuto in that situation and got the double play. Thought he did really good.”

“Felt good tonight,” Newcomb said. “It was coming out pretty good. You know, it didn’t go the way I wanted it to, but I was kind of able to makes some pitches, get out of a couple jams.

“There’s definitely a handful of situations where I had to buckle down. You always learn from that, so it’s good to have some of that coming and not have a bad outing.”

Unlike his first appearance, where Newcomb walked two batters, he walked four Friday. Three came in the sixth inning, when he seemingly ran out of gas. Snitker left Newcomb in to navigate a bases-loaded, no-outs trouble, and he limited the damage to a run.

“Bases loaded, got the double play,” Newcomb said. “Run still scored, which isn’t good, but I got the two outs and being able to get multiple outs there. One run through a couple bases-loaded situations is real good. Just making some pitches, getting some ground balls.”

Snitker acknowledged he left Newcomb in to see how he’d react to adversity.

“I kind of wanted to see how he’d do,” Snitker said. “How he responded, and I liked what I saw.”

Walks are an often-cited criticism: Newcomb walked 4.8 hitters per nine innings over his minor league career (5.2 in 2017). He walked 104 batters over 197 2/3 innings in the past two seasons. He ranked second in the International League in walks before his promotion.

Outside of Friday’s sixth inning, his command has been more consistent in the majors. He’s throwing strikes roughly 68 percent of the time. He’s also done well keeping the ball in the park. Justin Bour took Newcomb deep in the fourth — the eighth homer he’s allowed over his last 209 innings, and first he’s allowed in the majors.

“You never know,” Snitker said. “You move guys up, and he had good numbers and did good (in Triple-A), and you just never know how guys are going to respond. Early on, small sample size, he’s responded very well. I mean he’s been very composed, just kind of went about it, didn’t look like he’s awestruck by any stretch.

“Like I say, I’m seeing him getting after it and competing well, and his stuff’s really good. We saw the breaking ball tonight was good, and he was just (barely) missing. I don’t think he was wild. On some of the deeper counts he got he was just missing. And his fastball was live. Tough to get to when it’s in the strike zone.”

In a rarity, the strikeouts didn’t come for the lefty. After averaging 11.5 strikeouts per nine innings across 57 in Triple-A Gwinnett — and collecting seven in his first start in the majors — Newcomb fanned three against the Marlins. Braves starters rank last in the majors in strikeouts per nine innings.

Braves veteran second baseman Brandon Phillips said the offense let Newcomb down.

“He went out there and kept the ball down, did a great job,” Phillips said. “For him to be a young kid and just pitching the way he’s pitching — I don’t know if he was throwing 100; I don’t know what’s up with that radar gun out there, that’s crazy — but he pitched his butt off, man. It was nice to see, but it sucks that the bats didn’t get going. … He did a great job and didn’t have much to show for it.”

Miami came into the night with the fifth-best average against lefties in the majors (.272).

Newcomb finished with 106 pitches (67 for strikes). It was the most pitches he’d thrown this season, and the fourth time he hit the 100-pitch mark in 2017.

“I felt pretty good the whole time, got the adrenaline pumping a little bit,” he said. “I know I need to make some pitches right there, but yeah, it felt good, just kept trying to attack the zone, make them get weak contact.”

Newcomb is the first Braves pitcher since the team moved to Atlanta to lose his first two outings despite a pair of quality starts. He’s the first major league pitcher to do so since the Mets’ Jacob deGrom lost his first two quality starts in 2014.

Three quality-start losses to begin a career hasn’t occurred since Nels Potters for the St. Louis Browns in 1947.

Newcomb is the Braves’ No. 5 ranked prospect and No. 70 overall, according to MLB.com.