Forgive Braden Montgomery if he was darn near speechless after the White Sox claimed a 6-5 victory in 10 innings over the Braves on Tuesday night at Rate Field. The 23-year-old rookie just made history in his Major League debut, so he had reason to search a bit for that perfect explanation. Luckily for the White Sox, he was right on target against Braves closer Raisel Iglesias with two outs in the 10th inning. Montgomery connected on a second straight changeup from Iglesias, lining it out over the left-field fence for a two-run game-winner. The switch-hitter became the fifth player in Major League Baseball history to launch a walk-off homer in his MLB debut, joining Carlos Perez (2015), Miguel Cabrera (2003), Josh Bard (2002) and Billy Parker (1971), per Elias. “That was … I still don’t know what to say,” said Montgomery, standing in front of his locker after emerging unscathed from the postgame frenzy. “That was unreal.” “It was unreal,” echoed reliever Grant Taylor, who earned the victory by allowing one unearned run over two innings of relief. “That’s probably the coolest debut of all-time.” The heroics erased a 5-4 lead for the Braves (45-22) and came on the heels of Montgomery’s first career hit in the fourth, when he singled to left to also produce his first career RBI. Catcher Kyle Teel, who came over from Boston with Montgomery in the Garrett Crochet trade, was talking postgame of Montgomery’s great power the other way and wasn’t surprised by the direction of Montgomery’s connection. His 343-foot drive came in front of his parents and countless other friends and family members, after receiving the news of his promotion Monday from Triple-A Charlotte manager Chad Pinder. But here’s the real question for the No. 21 prospect overall and No. 2 for the White Sox, according to MLB Pipeline: What does he do for an encore? “I guess from here on out, it’s all downhill?” said Montgomery with a wry smile. “The highest of the highs. We’ll see.” “We all have this thought of what our debut is going to be like, and very few of us get to experience something like that,” said right-hander Erick Fedde, who allowed one earned run over five innings. “I'm really just happy for him, and all the hard work, he deserves it. I'm sure he won't forget this one.”