April 17, 1990: Bruins 3, Whalers 1
The Bruins made it all the way to the Stanley Cup Final in 1990, but nearly didn't get past their first round against the Whalers (pictured in 1996), their former Adams Division rivals.
The Bruins won a crucial Game 4, 6-5, after falling behind, 5-2, then seized the advantage in Game 5 with a 3-2 victory. Hartford won Game 6 in overtime, 3-2, before the Bruins closed out the series.
The Bruins went on to defeat the Canadiens in the division finals and the Capitals in the conference finals before losing to Edmonton, 4-1, in the Stanley Cup Final.