ST. LOUIS -- In awe of his surroundings and elated that he had just beaten out a slow roller up the third-base line for his first MLB hit, Cardinals rookie shortstop Masyn Winn was oblivious to all the drama that had just happened all around him as he stood at first base and tried to absorb the moment.

Winn, the Cardinals' top prospect, per MLB Pipeline, received boisterous cheers when his name was announced in the starting lineup and again when he made a diving play on a grounder in the top of the second inning, and his first at-bat was greeted with a standing ovation.

Seemingly oblivious to all of that was Mets first baseman Pete Alonso, who unknowingly tossed the baseball from Winn’s first hit into the Busch Stadium seats. The 21-year-old Winn, who was making his MLB debut following a Thursday night callup from Triple-A, admitted to being somewhat in shock at seeing the ball fly into the crowd and Cardinals players and fans being outraged.

Years from now, when he looks back at the baseball that he ultimately received thanks to work done by Cardinals security and plans to gift to his mother, Winn knows that he will have a story to tell and the memory of a lifetime.

“I think everybody will remember their first big league hit or first big league strikeout, and I’m super excited that I got the ball back,” said Winn, who went 1-for-4 in the Cardinals’ 7-1 loss to the Mets at Busch Stadium. “I was trying not to crack up laughing as soon as I heard [Busch Stadium fans yelling for the ball to be returned]. It was very funny, and I’m really glad [she] gave it back and that I got to sign a ball for her.”

To his credit, Alonso apologized to Winn right after the rookie recorded his first hit and again later at second base.

The whirlwind following his first MLB hit capped a frenetic 24 hours for Winn, a second-round pick from the 2020 MLB Draft who hit a 412-foot home run for Triple-A Memphis on Thursday night, found out he had been promoted to the big leagues and then drove the fourish hours to St. Louis for his debut on little to no sleep.

The Cardinals wasted no time in seeing what they have in the high-energy talent by immediately inserting him into the starting lineup. At 21 years and 150 days in age, Winn became the youngest Cardinal to make his MLB debut at the starting shortstop position since Garry Templeton (20 years, 138 days) on Aug. 9, 1976.

“Man, it was fantastic,” Winn said of the night when he had about 15 family members in the Busch Stadium crowd for his debut. “Walking out there and seeing the fans, I was a little bit nervous at first. But it was a lot of fun, and I’m really excited for the future.”

Winn got the callup after hitting .288 with 18 home runs, 61 RBIs and 17 stolen bases this season with Triple-A Memphis. Manager Oliver Marmol said he plans to use Winn only at shortstop even though the talented fielder split time at short and second base in Memphis.

Winn’s first call upon getting promoted late Thursday was to his mother (Tiffany Rawson) and stepfather (Earl Luckett) in Texas to alert them so they could make travel arrangements from Houston to St. Louis, which they hurriedly pulled off.

“We were actually asleep because it was 10:30 at night, but then it was this big explosion of emotion in the house, and we were like, ‘Wow, he finally did it, and his day has come,’” Luckett said while on the field at Busch Stadium.

Winn’s next call was to Cardinals rookie Jordan Walker, the player the franchise drafted before him in the 2020 MLB Draft. The two consider themselves to be “brothers” because of the time they have already spent playing together in the organization. Last season, when they were roommates and playing for Double-A Springfield, they openly dreamed of the days when they would lead the Cardinals to a World Series title.

“I let [Walker] know, and he started screaming and wasn’t really saying words with a high-pitched scream,” Winn said. “We talked for a little bit, and he let me know I was going to be fine up here.”

Said Walker: “All through the Minor Leagues, all we talked about was, ‘Wait until we get to the big leagues!’ I’m just excited to be here with him now.”