DENVER – Braves officials are confident that hard-throwing rookie Mike Foltynewicz could succeed as a late-innings reliever, and he demonstrated why Thursday night against the Rockies in his second relief appearance for Atlanta.

After giving up one run on three consecutive hits to start the fifth inning, Foltynewicz retired the last six batters he faced in order, including four strikeouts, topping out at 99 mph. The rangy right-hander used that power arm to get out of a tight jam, not allowing another run when the Rockies had runners at second and third with none outs. Strikeout, strikeout, fly ball. End of inning.

At moments like that, it’s easy to see why Foltynewicz, 23, was considered an elite prospect when the Braves got him from the Astros as a big piece in the Evan Gattis trade in January, and why he’s at or near the top of the Braves’ ever-increasing stockpile of young arms.

“Absolutely,” said veteran catcher A.J. Pierzyski. “He’s got electric stuff, we’ve always known that. Bottom line, he just needs to harness it. I mean, he’s still a work in progress, especially in the bullpen. But if he harnesses it, he can definitely be a weapon.”

That two-inning appearance Thursday was his second as a reliever since being recalled this week from Triple-A Gwinnett, where Foltynewicz was sent after going 3-2 with a 5.19 ERA in nine starts for the Braves.

While the ERA, .305 opponents’ average and eight homers allowed in 52 innings as a starter obviously weren’t great, his 48 strikeouts (with 17 walks) as a starter were impressive. And Foltynewicz’s ability to maintain his stuff deep into some of those games is what separates him from plenty of other prospects, in the Braves’ view.

It’s why they intend to keep developing him as a starter for the forseeable future, even if they know he might make an effective setup man or closer someday if they choose to go in that direction.

“We know he can do that (bullpen) role,” Gonzalez said. “There’s no question in our minds he can do that role. But it’s an easy move for us in the organization to say, ‘Hey, you’re a bullpen piece.’ Which, for us, it could always be there. (But) let’s try to develop him as a starter, see if there’s something there. I mean, there’s not too many guys that are starting that are 96, 97 miles an hour, carrying it through seven, eight innings.

“That, what we saw yesterday, for me we can do that anytime we want (with him). Why not try to develop him into a starter and give him the innings, and try to develop pitches, and see what happens? It’s hard to find major league starters at 97, 98 (mph). And this guy may or may not be able to do it. Why not take the time and effort to see if he can do it or not.”

Before this season, Foltynewicz’s only major league experience had been 16 relief appearances for the Astros in August and September.

“He looks like a seventh- or eighth-inning guy,” Gonzalez said. “Even the way he just walks around. He’s got the look, he’s got the (facial hair), he’s got the whole aura that you want. He is what a major league reliever looks like. From all the guys we threw out there yesterday, he looks like it.”