BOSTON – Austin Prep scored in the first and last minutes of the game but, in between, Malden Catholic dominated and claimed its third consecutive Division 1A championship, 3-2, Sunday night at TD Garden.The Lancers (16-6-3) joined Catholic Memorial as the only teams in the tournament’s 23-year history to win three titles in a row. Malden Catholic, which at one point this season was a game under .500 and finished last in the Catholic Conference with just a single league win, closed the season with 11 consecutive wins.Nolan Vesey’s first goal, off the game’s opening faceoff, gave Austin Prep a 1-0 lead with just 14 seconds expired. The Lancers responded by unleashing a withering attack that produced a 38-14 edge in shots. Only the play of sophomore goalie Elijah Harris (35 saves) kept the Cougars within striking distance.Goals by junior Tyler Sifferlin, at 5:25, and sophomore Austin Goldstein, at 13:00, gave MC a 2-1 lead by the end of the first period. Following a scoreless second period in which Harris had 15 saves, MC sophomore Ara Nazarian’s goal at 2:24 of the third period stood as the game-winner. Vesey made it 3-2 with 26.5 seconds left in regulation.Austin Prep, coached by Lou Finocchiaro of Saugus, had its 13-game unbeaten streak (10-0-3) snapped and finished 16-2-6.