Bruins center Patrice Bergeron played only 49 seconds in the second period and did not return to the game.
"Let's say right now we're going to give him a little time," Bruins coach Claude Julien told NBC's Pierre McGuire.
Bergeron appeared to be skating gingerly during a brief final shift before returning to the Bruins' bench.
He was on the ice for 6 minutes, 6 seconds total, including nine shifts in the first period and just two more in the second.
The Bruins announced via Twitter that Bergeron left the building and was hospitalized:
Update: Patrice Bergeron has been taken to a local hospital in Chicago for observation. There is no further update at this time. ^BB
— Boston Bruins (@NHLBruins) June 23, 2013