The league's top defensemen are vying for a shot at the Norris Trophy and, more importantly, the Stanley Cup, and many contending teams are in the running because of their talent on the blue line.
Being an elite defenseman is a tricky task. Whatever offensive skill you possess cannot be outweighed by ineffectiveness in your own zone. Gambling by pinching in to try to create a scoring chance can easily lead to odd-man rushes going the other way.
We are more than a quarter of the way through the shortened 2013 NHL season, and the contenders and pretenders are beginning to take shape.
Let's take a look at the 20 best defensemen in the NHL and see whose stock is on the rise this season, and who seems to be over-the-hill or on the decline.