HARTFORD, Conn. — For as long as they’ve been with the organization, Marcelo Mayer, Roman Anthony and Kyle Teel have been viewed as cornerstones of the Red Sox future.

All three were top draft picks and are usually lumped together by fans and evaluators, but it wasn’t until this past winter that the trio actually connected as a group for the first time.

They’ve been nearly inseparable since.

From the Red Sox rookie development program to Winter Weekend to spring training and now the top of the Portland Sea Dogs order, Boston’s “big three” prospects have begun forging a strong connection on and off the field. Each has enjoyed a terrific start to the new season, and the club hopes the seeds being planted now will continue bearing fruit as the group advances closer to the major leagues.

“We clicked right away,” said Anthony, a 19-year-old outfielder ranked as the No. 21 prospect in baseball, according to MLB Pipeline. “The more time you get to spend with those guys, the more time you play with them on the field, you continue to get closer and closer and it makes it that much more motivating to get to the top with those guys and win with those guys.”

“Those three feed off each other,” said Chad Epperson, the Portland Sea Dogs manager.

Though all three had prior experience at Double-A, this season marks the first time they’ll have a real opportunity to show what they can do at the level. Last season Mayer was hampered by a shoulder injury that limited him to a .189 average over 43 games, and Anthony and Teel each spent about two weeks in Portland at the end of the season.

Now fully healthy, Mayer has gotten off to a torrid start. Ranked as MLB Pipeline’s No. 14 prospect, he opened the season with a 10-game hit streak and entered Thursday batting .317 with two home runs, eight RBI and an .844 OPS. He had one of the best games of his career on Wednesday, going 3 for 4 with a home run, a double, a walk and three runs scored in Portland’s 7-4 win over the Hartford Yard Goats.

“He’s playing with a bit of a chip on his shoulder,” said Brian Abraham, the Red Sox director of player development. “You usually don’t say that about a prospect of his caliber but he wants to prove to himself, prove to others, prove to us that he’s the player we all think he can be, and should be.”

Epperson said Mayer’s talent has always been evident but last season his bat speed just wasn’t there. Now he’s in a much better spot, and though it’s tantalizing to imagine Mayer emerging as a solution to Boston’s infield injury woes, the 21-year-old shortstop isn’t getting ahead of himself.

“Hopefully I can continue to play well but I’m not focused on the future too much,” Mayer said. “Obviously I want to be a big leaguer, I think about it every day, but in order to get to where I want to be I need to handle business here first.”

So far Mayer has primarily batted second for the Sea Dogs, with Anthony leading off and Teel batting third. It’s a tempting look at a possible future for the Red Sox, one fans didn’t get to see last year because Mayer had already been shut down by the time Anthony and Teel were promoted to Double-A in September.

Their cameo in Portland was brief but impactful.

“They were here for about two weeks but it feels like they were here for about two months the way they’ve adjusted to the upper levels,” Abraham said.

Teel was only about a month into his professional career when he got the call to Double-A, a rapid rise for the 22-year-old catcher after being taken No. 14 overall out of Virginia in last summer’s draft. Before he got there, however, he connected with Anthony at High-A Greenville, which is where their friendship first formed.

“When I got called up there from the complex, he’s younger than me but he was still showing me around and showing me how things are done there,” said Teel, baseball’s No. 37 prospect. “It was really nice, he was really open with me and I’m grateful for that.”

Beyond being immensely talented ballplayers, the trio can also relate to one another when it comes to managing the pressure that comes with being such a highly touted prospect. Red Sox officials haven’t been shy about their belief that Mayer, Anthony and Teel will one day become foundational parts of a championship contender, and for all the hype that has followed them throughout their careers, each still has a long way to go.

But that’s a path they’ll walk together, and so far they’ve looked every bit the part.

Zeferjahn turns heads

Coming into the season, the Red Sox hoped to see some of their minor league arms take a major step forward, and so far it appears Ryan Zeferjahn is making the leap. The 26-year-old right-hander has been dominant for the Sea Dogs out of the gate, and entering Thursday he had posted a spotless 0.00 ERA over his first 7.2 innings with 11 strikeouts against one walk. A Red Sox front office source singled him out as someone who has raised eyebrows, and Abraham said he had a great offseason and is seeing impressive early results.

“The focus for him was throwing strikes, being competitive in the zone,” Abraham said. “It’s only been a short amount of time this year but he’s done that.”

Two other arms who have gotten off to strong starts are Zach Penrod and Connelly Early. Penrod had a 0.00 ERA with 14 strikeouts and three walks over 10.1 innings through his first two starts in Portland, and Early has a 2.13 ERA with 18 strikeouts over 12.2 innings through his first three starts at High-A Greenville.

Early, a 22-year-old left-hander who was taken in the fifth round of last summer’s draft, was also a college teammate of Teel’s at Virginia.

“It doesn’t surprise me at all that he’s having the success that he is,” Teel said. “It’s really nice to see.”

Odds and ends

Luis Perales (ranked No. 9 in Red Sox system by MLB Pipeline) has so far only made two appearances with High-A Greenville and none since April 12. Abraham said the 21-year-old righty has been dealing with side soreness but nothing serious enough to warrant an IL stint.

“With his arm and being on the 40-man just wanted to be overly cautious to make sure he’s 100 percent healthy,” Abraham said. “He’s been throwing live and he’ll have a start in the very near future.”

Shortstop Mikey Romero (No. 11), Boston’s top pick in 2022, has yet to debut as he works his way back from the back injury that derailed his 2023 season. He’s working out in Fort Myers but Abraham said he’s in a great spot and has been swinging the bat and moving around well.

Fellow shortstop Yoeilin Cespedes (No. 7), the club’s top international signing in 2023, has battled some quad soreness but is expected to be ready to go for the start of the Florida Complex League season on May 4.