The Chicago Blackhawks eliminated the Nashville Predators in six games, but their Western Conference First Round series went the distance in terms of drama and ice time.

The Blackhawks eked out three one-goal wins, including two in overtime games that totaled 68:49 beyond regulation. It took more than seven regulation periods for the Blackhawks to oust the Predators from the 2015 Stanley Cup Playoffs, including a Game 1 win in double overtime and Game 4 win in triple overtime.

Even discounting an empty-net goal for the Predators at the end of their 5-2 victory in Game 5 at Bridgestone Arena, Chicago was outscored 21-19 and needed each goalie to step up. Nashville lost captain Shea Weber to a lower-body injury in Game 2 and had center Mike Fisher for two-plus games, but the Predators still put more shots on goal in four of the six games.

How did Chicago win? Here are five reasons the Blackhawks advanced to the second round:

1. The core group – Chicago's management group continues to be rewarded for locking up its central cast. Whenever the Blackhawks are in tough spots, it's almost always the "core group" that saves the day.

When they needed a goal in double overtime of Game 1, two-time Norris Trophy winner Duncan Keith scored it. When they needed a win in Game 3, the top line centered by captain Jonathan Toews delivered. Defenseman Brent Seabrook scored the third overtime playoff goal of his career 1:00 into the third overtime of Game 4, and Game 6 featured goals by Toews, Keith, Patrick Kane and Patrick Sharp to clinch it.

2. Goaltending depth – There are two ways to look at what happened with Corey Crawford and rookie Scott Darling. You look at coach Joel Quenneville see-sawing between the two as a weakness, or you could look at it as two solid goalies who give the Blackhawks almost unmatched depth in net. Crawford started the series shaky by allowing nine goals in his first four periods, but Darling was there to put up a 6-foot-6 brick wall in Games 1, 3 and 4, all victories. When Darling faltered late, Crawford returned to finish off the Predators in Game 6. Nashville didn't have the same luxury with Pekka Rinne, who wasn't in top form.

3. Playoff experience – Much was written and talked about before, during and after the series regarding the Blackhawks' decided edge in playoff experience. Ultimately, that is what prevented a first-round loss to the Predators. Nashville overwhelmed Chicago in each of its victories, and even prompted the aforementioned goalie swapping with a 6-2 win in Game 2.

Either one of the Predators' victories could've sunk a less-experienced team, but the Blackhawks remained calm and confident each time. They responded with wins after each defeat, and their vast experience in overtime likely helped them win Games 1 and Game 4.

4. Puck possession – Prior to the series, coach Peter Laviolette told the Predators that puck possession would be the No. 1 key to beating the Blackhawks. He turned out to be right, because the Predators failed to win that battle.

The Predators did a good job frustrating Chicago with speed and aggressiveness to force turnovers and odd-man scoring chances for themselves. They even outshot the Blackhawks 232-208. What they didn't do was control the puck enough. Chicago finished the series with a shot attempts percentage (SAT%) of 53.3 percent during 5-on-5 play to 46.7 percent for Nashville.

5. Duncan Keith – Many adjectives have been used to describe his remarkable ability to play a lot without suffering a drop in his play. It's hard to argue with any of them when you look at the last three games of this series.

Keith played 46:19 in the Blackhawks' triple-overtime win in Game 4. Two days later, he topped all players in Game 5 with 27:08 and logged a game-high 28:00 in Game 6 while scoring the game-deciding goal late in the third period and adding two assists. Of the 221 minutes played in the final three games, Keith was on the ice 45.8 percent of the time (101:27).