There's something about a nasty player feud that brings out the blood lust in fans.
The sight of the Flyers' logo in Pittsburgh or a glimpse of Sidney Crosby and Evgeni Malkin in Philadelphia means that a fevered battle is at the ready. The fans simply despise the opposing team and want to beat them badly.
However, the stakes go up when players get caught up in the intensity. For example, Sidney Crosby may be the best player in the league when he's healthy. He hasn't been in top form for a while because of concussion-related issues.
During his long convalescence, Claude Giroux has continued to thrive and grow in Philadelphia. His head coach Peter Laviolette has promoted him as the best player in the league. As a result, whenever Crosby and Giroux play against each other, emotions have a tendency to be on display.
During last spring's playoff series, there was no backing down from either player, and there's likely to be further displays of temper and tension in upcoming seasons.
Here's a look at eight other notable player rivalries.