Ullmark made 22 saves in Thursday's 6-3 win over the Bruins.
Ottawa struck four times in the first period, chasing Jeremy Swayman from the game and giving Ullmark a big early cushion as he picked up a win against his former club. Ullmark has yet to take a regulation loss in March, going 5-0-1 with a 2.80 GAA and a .913 save percentage, and the surge has helped the Senators tighten their grip on a playoff berth -- they're five points up on the Blue Jackets and Rangers in the race for the first wild-card spot in the Eastern Conference.