But Kelleher is not just the captain, he is one of the team's standout players and one of only two returning starters from last season.
"[He's] been an All State player for two years in a row and he brings great leadership and ability," Mull said. "He's also on the watch list for the All American team, which plays in December down in Philadelphia, (Pa.) at the Philadelphia Union Stadium. He's being looked at by UVM and other DI programs so he's definitely the real deal and he'll bring a lot to the table."
Kelleher sustained the injury while playing in a game as a member of the Southern Vermont All Stars two weeks ago when they faced the Vermont Voltage at Applejack Field. Although he originally he thought it was a charlie horse, Kelleher said the injury continued to become stiff and swollen.
A trip to the doctor's office revealed that he had a hematoma - or blood clot - in his leg that was about the size of a golf ball, Kelleher said.
While no definite timetable has been set for his return, Kelleher said he is hopeful that he will be well enough to take the field for the team's first match against Mount Anthony Union High School on Sept. 4.
"The doctor said it should take a week or so, but it all depends on how it heals," said Kelleher. "You know I hope to be back and running again by the first game, but you know we'll see. I mean that's Sept. 4 and I hope to be back to normal by then."
Having Kelleher in the lineup would certainly help the team who will be facing a tougher schedule this year with the move up to Division I.
Starting with MAU, the Bulldogs will play three games in four days. In addition to MAU, BBA will also play Mount Greylock and Monument Mountain - two of the better programs in western Massachusetts, Mull said - at a tournament.
"We don't have teams like Otter Valley and Fair Haven, they're the B division of the Marble Valley League conference now," Mull said. "There's just not going to be any breaks in our schedule. It's going to be one tough game after another."
Burr and Burton won back to back titles over the past two seasons, which included a perfect season last year that was capped with a 2-1 win over Montpelier.
Coming into this season, BBA will likely also rely heavily on the other returning starting member of last year's squad - junior Reid Condi who was the Bulldog's leading scorer last year with 17 goals.
So far this preseason, Kelleher said he has already seen Condi step up a lot.
"Already this preseason [he] has taken a lot of leadership out on the field," said Kelleher. "When he sees someone doing something that might be just off or whatever he'll give them that talking and say 'here, you've got to pressure this guy when ...' He's definitely taking leadership on the field."
In addition to the players that he has been working with in preseason, Mull said that BBA also has some international students that will be joining the team. At the moment, Mull said that there are two that he is aware of - one from Barcelona, Spain and the other from Brazil - that will be joining this year's squad. However, Mull said it is unclear at this time what their skill level is.
With only six returning players this year, Mull said it is unclear who will mind the net, but that junior Adam Maitland has been getting significant time in the preseason as keeper.
"He's been getting a good look at it and has been playing most of preseason in the goal, but we're also looking at a freshman, James Doherty. So, those two guys will fight for time between the pipes," Mull said.
This year's team will be a young one, Mull said with only four seniors, three sophomores and potentially even a freshman projected to be in the starting lineup - something Mull said he did not mind.
"We'll be very young, but one of the nice things about that is the younger teams tend to develop more quickly as the season progresses," Mull said. "We're young and skilled and we just need to learn to play with each other."
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