2. Pittsburgh Penguins
Some might find this shocking, but the Senators have a deep rivalry with the Pittsburgh Penguins. In another shocking twist, the Senators have played the Penguins the most in the Stanley Cup Playoffs with five meetings. The playoffs is where hatred began.
2007 was the first time the two teams met in the playoffs. It was Sidney Crosby's second NHL season. The Senators knocked off the Penguins in five games in the first round. The Senators fell in the 2007 Stanley Cup Finals. Now, the irony would happen the following year.
In the 2008 Stanley Cup Playoffs, the Senators were matched up with the Penguins again, but this time the Senators were swept. The Penguins later on would lose in the Stanley Cup Finals in 2008. It's interesting that when both teams fell in the Stanley Cup Finals, they defeated each other in the opening round of the playoffs.
The Penguins knocked off the Senators in the 2010 first round and 2013 second round. In 2017, they gave hockey fans a thrilling series in the 2017 Eastern Conference Finals.
With the series tied at two, hope appeared gone for the Senators when they lost 7-0 in Game 5, but the Senators responded with a 2-1 win in Game 6 to set up a Game 7.
Justin Schultz scored a powerplay goal to give the Penguins a 2-1 lead with 8:16 to go. Hope looked gone for the Senators until Ryan Dzingel tied the game less than three minutes later. Overtime was needed for the two teams. The winner was going to the Stanley Cup Finals against the Nashville Predators.
Earlier, the name of Jeff Friesen was mentioned for his late go-ahead goal in Game 7 in 2003. If you mentioned the name of Chris Kunitz to any Senators fan, they will most likely cringe. Kunitz scored the series-winning goal in double overtime to end Ottawa's cup chase.
Since that loss, the Senators haven't been back to the playoffs. The Penguins put a dark cloud over Ottawa with that Game 7.