The Bears will now move on to the Eastern Conference Finals, where they await the winner of the Atlantic Division Finals series between Worcester and Manchester.
For the fourth time in four games this series, Hershey had to stage a third-period comeback to put itself in a position to win. This time, the Bears trailed 4-2 by the 10:19 mark of the frame before Alexandre Giroux (16:37) and Perreault (18:47) struck late to send the game to overtime.
The Bears prevailed in the series despite holding a lead for only 10.6 percent of the total hockey played, or 28:39 of action.
Bourque tied it at 2-2 with his second power play goal of the night just 59 seconds into the second frame, only to watch Zach Boychuk score unassisted at 10:31 to restore the River Rats’ lead.
Boychuk added another unassisted tally midway through the third period to make it a 4-2 game, but it was all Bears from that point on.
Thursday’s loss brings the curtain down on the River Rats franchise’s 17-year old stay in Albany. The River Rats, who won the Calder Cup in 1995, will relocate to Charlotte, N.C., for the 2010-11 season.