Zdeno Chara and Johnny Boychuk scored 2 minutes, 20 seconds apart in the second period to break a scoreless tie, and Recchi assisted on the second goal to give him 1,532 points — one more than Paul Coffey. Nathan Horton made it 3-0 in the third.
It was the 25th shutout of Thomas' career, and his second in three games. He has allowed just two goals in four games to drop his league-leading goals-against average to 1.96.
Corey Crawford made 31 saves for the defending Stanley Cup champions, who had won three of four but remained three points ahead of idle Calgary for eighth place in the Western Conference.
The Bruins protected their lead over Montreal atop the Northeast Division and moved three points behind the Washington Capitals in the race for the No. 2 seed in the East.
One night after an overtime victory in Detroit, the Blackhawks started slow and didn't get off a shot for the first 7:44. It was still scoreless when the Bruins took a faceoff in the Chicago end with just over 8 minutes left in the second. The puck came out to Chara at the left point, and he wristed it past Crawford to make it 1-0.
Boychuk made it 2-0 with a knuckleball that Crawford seemed to lose track of. It stayed that way until the third, when Daniel Paille chased the puck toward the corner and backhanded it through the slot to Horton, who stickhandled to Crawford's glove side and shot the puck past him.
Notes: Bruins F Shawn Thornton left the game with a cut after taking a skate to the head in the second period. He didn't return. ... Boston's minor league affiliate in Providence of the AHL signed 2009 third-round pick Ryan Button to an amateur tryout agreement. ... It was the Bruins' last game against the Western Conference. They finished the season 8-7-3. ... Recchi has 576 (19th) goals and 956 (13th) assists in his career. ... Crawford made his 21st consecutive start and the first appearance of his career against the Bruins. ... Horton reached 50 points for the fourth time in five seasons. ... The Blackhawks lost to a Northeast Division team for the first time this season (4-1).