WORCESTER — As Marcelo Mayer, Roman Anthony and Kyle Teel walked into the DCU Club at Polar Park, they were greeted by a crush of media not often seen at a Triple-A ballpark.

But then again, you don’t see a group like this come along often either.

Mayer, Anthony and Teel, the Boston Red Sox’ top three prospects who have collectively become known as the Big Three, made their long anticipated arrival in Worcester on Tuesday. The highly touted trio was promoted to Triple-A as a group over the weekend, putting them just one step from the big leagues.

“It’s a dream come true,” said Teel, a catcher who was selected No. 14 overall in last summer’s MLB Draft. “I’m so grateful and it just shows the hard work paying off.”

The three were informed they were being promoted on Sunday night. They were called into Sea Dogs manager Chad Epperson’s office, which tipped them off something was up, but before spilling the beans he first joked that there was going to be a prospect camp in Haiti and that they’d all be going.

“We knew he was kidding,” said Mayer, a shortstop who ranks as MLB’s No. 10 prospect according to Baseball America. “It was a really special moment, to get the call up and especially with these two guys here, we’ve been together all season and it’s been fun.”

While the Big Three have always been linked in the eyes of fans by virtue of being former top draft picks who blossomed into consensus top 100 prospects, that connection became much more tangible this past winter. The three spent time together over the offseason taking part in the Winter Weekend fan fest and the club’s rookie development program, and since the season began they’ve become inseparable.

The Red Sox saw that connection blossom and decided to lean into it by moving them up together.

“As an organization and as a player development group, if we didn’t take into account their friendship, the way they react and interact with their teammates, how they push each other and challenge each other, I think we’d be doing ourselves a disservice,” said Red Sox director of player development Brian Abraham. “It doesn’t always work out this way so to be able to take advantage of it, we thought it was worth it.”

“It’s definitely awesome and it makes it easier to go out there and play with your best friends,” said Anthony, who at 20 years old is the youngest Red Sox prospect to reach Triple-A in decades.

The three arrived in Worcester on Monday, and knowing how chaotic their first day could potentially be, WooSox manager Chad Tracy had them come to the ballpark much earlier than usual on Tuesday so they could meet one on one, learn the team’s signs and get integrated as quickly as possible.

He also wanted to make sure they understood what kind of situation they were stepping into and what would be expected of them.

“I told all three of the kids, this is finishing school now,” Tracy said. “You’re talented, you go through A-Ball and Double-A and your talent carries you, now this is where you have to start thinking along with the pitcher, they’re going to be able to execute things that they can’t in Double-A, all those little things.”

Mayer, Anthony and Teel have all performed exceptionally well this season, to the point where they could have reasonably earned promotions months ago. But while they’ve often been among the youngest players in their respective leagues, they are now set to compete against grizzled veterans, many of whom have big league experience.

The jump from Double-A to Triple-A is big, and it’s one the Big Three will make under an intense spotlight. Few prospects in recent Red Sox memory have been as highly touted as these, but while Mayer, Anthony and Teel feel that pressure, it’s nothing they haven’t already been dealing with throughout their baseball lives.

“Yes, there is pressure, and it is uncomfortable, but at the same time I don’t look at that as something that’s negative by any means,” Teel said. “You have to embrace that feeling and do what you’ve got to do every day.”

Mayer day-to-day

While Mayer was activated from the seven-day injured list after sitting out a week with what the club described as hip irritation, the shortstop wasn’t in the lineup for the WooSox alongside Anthony and Teel. He’s described as day-to-day, and during Tuesday’s press conference he shed light on what he’s been dealing with lately.

“I’m feeling much better, my lower back and upper glute area were bothering me a little bit. I missed the week in Somerset due to some soreness and my back flared up on me,” Mayer said. “So we’ve been cautious with it, don’t want to play on a back that’s hurt and I end up getting more hurt than I need to. We’ve been taking it pretty slow but I feel good.”

Mayer had a doctor’s appointment in Boston on Monday, and Tracy said he should soon start taking batting practice and ground balls before hopefully making his Triple-A debut by the end of the week.

Casas crushes homer

Prior to the game Tracy offered a positive assessment of Triston Casas’ progress, saying his timing has gotten better with each passing game and that he’s made a number of nice defensive plays at first base during his rehab assignment.

One thing he hadn’t done yet is hit a home run, but Tuesday he ended that drought in a big way.

Casas hit a two-run home run his first time to bat in the bottom of the first, crushing a 90 mph sinker 402 feet to right field that sailed out of Polar Park. He scored Anthony, who two batters earlier had doubled in his first Triple-A at bat.

Gasper draws praise

When Mickey Gasper stepped to the plate with the game on the line in the bottom of the 10th inning for his MLB debut on Monday night, his former coaches and teammates in Worcester were glued to their screens. Tracy said he woke up his wife he was so fired up, and prior to Tuesday’s game he offered high praise for the new Red Sox call-up.

“His at bats are as good as I’ve seen in my three years here,” Tracy said. “To see him step up, and most impressively, walking in that spot in his big league debut in a chance to win the game and being disciplined enough to look for a strike and he didn’t get it and he passed the baton. … It was really cool.”

Gasper batted .402 with a .515 on-base percentage and a 1.179 OPS in 40 games following his promotion to Triple-A, and normally that level of production is unsustainable, even for the best hitters. Tracy said he thought that would be the case too, but as the games went on he and his coaches began to realize it wasn’t a fluke.

“It’s as good as a pure hitter as I’ve seen here. His ability to go line to line, take a two strike pitch and slice it inside the third base bag, if you make a mistake he hits hit 430 feet to right field,” Tracy said. “Tons of contact, doesn’t expand outside the strike zone, it’s been impressive to watch.”