Paul Skenes - Olivia Dunne's boyfriend - has allowed his first ever home run in a pro baseball game while pitching for the Pittsburgh Pirates' Triple-A affiliate. 

Skenes, 21, gave up a solo home run to Buffalo outfielder Will Robertson - a Toronto Blue Jays prospect - in the fifth inning of an 8-3 win for the Indianapolis Indians on Sunday against the Bisons. 

Skenes had pitched 33 2/3 innings in the minor leagues over the last two seasons before conceding his first long ball. 

But the first overall pick of the 2023 MLB Draft didn't let things get to his head, as he got one more hitter out on Sunday before leaving after 4 1/3 innings, having allowed two runs on three hits with four strikeouts and two walks over 66 pitches. 

What's more is that Skenes' ERA jumped up to just 0.99 despite allowed two earned runs for the first time this season. He has allowed four total runs (three earned) on 17 hits with 45 strikeouts and eight walks over 27 1/3 innings since March. 

Top MLB prospect Paul Skenes conceded his first homer against the Buffalo Bisons on Sunday

Buffalo outfielder Will Robertson - a Toronto Blue Jays prospect - hit a solo homer in the fifth

Skenes' Indians still won the game, 8-3, despite the pitcher showing weakness for the first time

Define "success."

After a successful challenge of a 3-1 ball call, Paul Skenes yields his first homer as a professional on the very next pitch -- his second slowest fastball of the year (97.9 mph). pic.twitter.com/VagybAHety

— MLB Pipeline (@MLBPipeline) May 5, 2024

Senes and LSU gymnast Olivia Dunne in a photo she posted on Instagram in November 2023

The Pirates are expected to call-up Skenes at one point during the 2024 MLB season but are sticking with their plan for the right-hander to develop in the minors for one more year, despite his dominance in Triple-A games, so far. 

Skenes played in some of Pittsburgh's pre-season games in Florida, earlier this year. 

'We talk about boxes being checked, and today would be another one,' said Pirates general manager Ben Cherrington before Skenes' start on Sunday, according to 93.7 The Fan. 

'It's the first time, as a professional... that he'll be starting a game on four days' rest. It may not seem like a big deal, but it is the first time it'll happen, and it's another box to check. 

'He's been checking just about every box since the season started and is responding incredibly well.'