CHICAGO -- If you accounted for how little AJ Smith-Shawver had pitched in high school, it was unreasonable to expect him to taste immediate success last summer, when he arrived at the Major League level at just 20-years-old.

Now a year older and seasoned by last year’s valuable experiences, Smith-Shawver appears ready to live up to strong expectations. The 4 1/3 innings he threw in a 3-0 win over the Cubs on Thursday afternoon at Wrigley Field showed why MLB Pipeline regards him as the Braves’ top prospect and the Majors’ No. 58 prospect.

“He’s a freak athlete,” Braves reliever A.J. Minter said. “To see it all come together and pay off this year is really good. He’s going to be a big part of this team moving forward and for the future.”

Smith-Shawver scattered three hits, including a pair of infield singles, over 4 1/3 scoreless innings. He tallied two of his four strikeouts in the first inning and renewed the excitement he created in Spring Training, when he leaned on a changeup, a pitch he rarely used last year.

“The kid is making progress,” Braves manager Brian Snitker said. “He’s getting better and maturing. His secondary stuff was a little better than what I was expecting.”

This might have been just a spot start, but Smith-Shawver proved to the Braves and himself that he can now be successful at this level. Everyone has known about his tremendous arm strength going back to his high school days, when he was throwing footballs 70-plus yards and drawing offers from schools like Texas Tech.

So it wasn’t necessarily a surprise to see Smith-Shawver’s four-seam fastball touch 99.3 mph and average 96.2 mph during this 87-pitch outing. But it was encouraging given the same pitch averaged 94.5 mph last year.

More encouraging was the success he had with both the changeup and the curveball. Opponents hit .364 with a .636 slugging percentage against the curve last year. He got a called strike with five of the 18 curves he threw on Thursday, with the Cubs putting this pitch in play just twice -- Dansby Swanson’s infield single in the fifth and Michael Busch’s groundout in the fourth.

As for the changeup, it was all the rave in Spring Training because it was obvious he was going to lean on this offspeed delivery after throwing it just 10.6 percent of the time last year. The Cubs whiffed with three of seven swings against the changeup and put just one in play -- Seiya Suzuki’s single in the first.

“I definitely feel like I can get the job done here,” Smith-Shawver said. “I’m confident in my stuff. It's just about getting opportunities and trying to make the most of them.”

Jarred Kelenic’s leadoff homer in the fifth inning backed Smith-Shawver’s effort and helped the Braves to win this three-game series. Kelenic’s shot to right-center was one of just two hits recorded by Atlanta before Chadwick Tromp singled and scored on Ozzie Albies’ single in a two-run eighth.

Smith-Shawver and five Braves relievers combined to produce the team’s MLB-high eighth shutout. The Cubs have been on the wrong end of three of the four shutouts Atlanta has constructed within its past 10 games.

Smith-Shawver set the tone as he made this season debut a couple weeks ahead of the one-year anniversary of his June 4, 2023 MLB debut. He posted a 4.26 ERA in six appearances (five starts) last year and got a taste of the postseason when he came out of the bullpen after the Braves faced a steep deficit against the Phillies in Game 3 of the National League Division Series.

“The game feels a little slower compared to when I was out there last year,” Smith-Shawver said. “It felt like the game sped up on me sometimes last year.”

That was understandable. Smith-Shawver stopped pitching when he reached high school, because his focus was on football and because he was dealing with a growth plate issue in his right shoulder.

Smith-Shawver agreed to pitch in a game for a travel team during the summer of 2020 and immediately registered 93 mph on scouts’ radar guns. The Braves took him in the seventh round the following summer, gave him a signing bonus of nearly $1 million and then brought him to the big leagues less than two years later.

There’s a chance the Braves will send him back down for more development. But it looks like he could be an asset in Atlanta this summer.

“I saw him in the lobby today and I was like, ‘You know what, that's what they look like,’” Snitker said. “He's a big young strapping kid and he's an athlete. I think that's going to play well for him as he matures and learns the game and all the aspects. He's got an unbelievable upside.”