BOSTON -- For Brayan Bello, the most anticipated starting pitching prospect the Red Sox have had in years, the experience is what mattered.

You can only have one Major League debut.

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Ideally, Bello would have seized the moment and electrified Fenway Park with his impressive repertoire.

But it was not to be, as the No. 3 Red Sox prospect as rated by MLB Pipeline took the loss while lasting four innings in a 7-1 setback against the Rays.

Whenever Bello gets his next chance for Boston, the results will take on a bigger meaning. Wednesday night was about getting acclimated to the highest level of baseball.

When it was all over, the 23-year-old was still smiling.

“Yeah, it was a unique experience,” said Bello. “I was very happy to be out there, and every pitch, every batter was great. It was very emotional for me to be out there, and it’s not the last time I’m going to be out there.”

The confidence Bello spoke with sounded genuine rather than cocky.

He knows the work he has put in since the Red Sox signed him out of the Dominican Republic for a modest $28,000.

Bello was no bonus baby. Yet, he’s turned himself into a pitcher to follow going forward. A rocky debut, in which he gave up six hits, four runs and three walks while striking out two, did nothing to diminish Bello’s standing within the organization.

“Like I said [leading into the start], whether he went seven innings and gave up no runs, or three innings and seven runs, we still love the kid,” said Red Sox manager Alex Cora. “And we know what he means to this organization.”

Let the record show that the first pitch of Bello’s career was a 96 mph sinker that Josh Lowe looked at for strike one. His second pitch was popped to center, into the waiting arms of Jarren Duran. 

Reality struck quickly when Yandy Diaz stepped up next and belted a double off the Green Monster and Wander Franco -- who knows what it is like to be a top prospect -- ripped an RBI single up the middle. 

“Yeah, I didn’t really like my stuff at the beginning,” Bello said. “As the game went on, I got in a good rhythm with [catcher Christian] Vázquez and my stuff got better and that’s it.”

Bello had a scoreless second inning and a scoreless fourth. In between, the Rays tagged him for a three-spot in the third, scoring all of those runs with two outs.

Smiling as he spoke, Bello said nerves weren’t an issue.

“I just tried to be a little too selective, and that’s not who I am,” Bello said. “I like to be aggressive. I think that was the key.”

When Bello got his first Major League strikeout against Francisco Mejia for the second out of the second inning, the Red Sox tossed the ball back to the dugout. It eventually made its way to Bello’s locker and will be a souvenir he looks back on fondly at some point.

Did Bello take any other souvenirs with him from his first game?

“Yeah, I’ll take everything with me right here,” Bello said, as he tapped on his heart. “This is something you don’t get to do over again, so this is one time. I take everything right here.”

Though the Red Sox didn’t reveal their immediate plans for Bello after the game, it seems likely he will go back to Triple-A Worcester for his next start.

And those Minor League games will have a great meaning now that Bello has a better idea of how precise he needs to be to succeed in the big leagues.

“Yeah, I learned that they’re not the same hitters that you face down there in Triple-A,” Bello said. “You face batters who are very smart, selective hitters who are going to pick out the pitch they are going to hit, and that’s what I learned for my next outing.”

Bello also learned what the thrill of pitching at Fenway Park with a crowd of 33,735 cheering you on is like.

“It was a really exciting moment and, yeah, I was super excited to be here in front of the fans,” Bello said.

Even on what was far from his best night, Bello made it evident why his future should be bright.

“You see it,” Cora said. “You see his stuff, you see his sinker, you see the velocity and the poise. It just happens with two outs they scored all those runs. But whenever he gets a chance again, he's going to be better.”