The surprising season of the Senators: how did we get here?

For the casual Ottawa hockey fan — those who only begin paying attention once people start talking "playoffs" — the rise of the Senators this season may come as a surprise.

With a win tonight in Montreal, the Sens can overtake the Canadiens for first place in the Atlantic Division.

How did this happen? Here's a brief primer on what you missed, and why the best may be yet to come.

New coach, new system

The first rule of the system, is that you talk about it. All the time. Head coach Guy Boucher came aboard this year with a new system: clog the neutral zone to eliminate passing and shooting lanes for the opposing team and frustrate them in the process. Then, capitalize on quick counterattacks. Call it hockey's equivalent to the old catenaccio style of defensive soccer.

It requires buy in from both the stars and role players. This year, captain Erik Karlsson leads the league in blocked shots. Mark Borowiecki, meanwhile, leads the league in hits. They are buying in.

Karlsson being Karlsson

The two-time Norris trophy winner is on track to having another incredible season, arguably his best ever. So good that his coach says he should be in the running for MVP.

Not only is he amassing points at a Karlsson-esque rate (14 goals and 53 assists through 73 games) he's controlling opposing attackers and playing more when the team is down a man trying to kill penalties.

As CBC hockey commentator Shaila Anwar put it on Twitter: "Erik's just having a good time."

Goaltending depth

This season could have gone into tank territory in a hurry when starting goalie Craig Anderson announced he needed to take a leave of absence to support his wife Nicholle as she sought treatment for cancer.

Instead of hoping Andrew Hammond could replicate his Cinderella run of a few years back, general manager Pierre Dorion got on the phone and traded a fifth-round pick to Pittsburgh in exchange for Mike Condon. Condon more-than-capably minded the net until Anderson's return.

Now the Sens rank ninth in the league in goals allowed per game, and Condon and Anderson have combined for nine shutouts this year.

The new guys

Curtis Lazar was a popular player, but he had struggled this year, and at the trade deadline he was traded with Swedish defenceman Jonathan Dahlen and a third-round draft pick for what turned out to be a shot of adrenaline.

Speedy forward Viktor Stalberg and lifetime Vancouver Canuck Alex Burrows combined for 10 points in their first 12 games in Ottawa, and while Burrows has settled down after a torrid start, his timely scoring and peskiness could come in handy come playoff time.