It's perhaps the single most important factor in the success of teams playing in the "new NHL".
When you have it, you can seem almost invincible.
When you don't, you're easily beaten.
Depth comes in to play most heavily when the league is contracted to 16 teams in mid-April, and only increases in value as that group gets smaller.
We're far from mid-April, but depth seems to already be playing a critical role for the Detroit Red Wings.
On Sunday, Wings' forward Jan Mursak suffered a devastating ankle injury after sliding full-speed into the boards during the Wings exhibition home game against the Chicago Blackhawks.
Mursak, who was signed to an NHL-contract last season, figured to be a promising rookie this season, as his speed and tenacity were to have high replacement-value compared with what the Red Wings were losing upon the retirement of Kris Draper.
Though the battle for the bottom forward spots figured to be heated, Mursak had the inside track when competing with hopefuls Cory Emmerton and Fabian Brunnstrom.
Only a horrendous performance by Mursak, coupled with an all-world performance by one of the other two during the exhibition season, could have robbed Mursak of his shot at full-time employment in the NHL; or so it seemed.
With Mursak now gone a minimum of three months, according to Ken Holland, there exists not one, but two new openings at the forward position in Detroit.
One of these seems destined to go to Fabian Brunnstrom.
Brunnstrom's story is well documented, as is the fact the Red Wings were hotly pursuing the Swedish prospect in the summer of 2009, prior to his signing with the Dallas Stars.
Three-years removed from his first foray into the NHL, Brunnstrom found himself unsigned and largely unwanted this summer, which prompted him to solicit the Detroit Red Wings in hopes of securing a tryout contract.
They obliged him and were eager, if not a little apprehensive, to see if he'd be able to make a serious run at a contract.
Worst case, he'd fizzle and remain an NHL afterthought, best case, he'd provide the Wings with even more offensive depth; both the Wings and Brunnstrom had their hopes pinned on Option 2.
So far, so good.
Brunnstrom has looked quite good so far in the exhibition season and his size and puck-handling ability seem tailor made for a forward-corps that is lacking a bit of the former but all but requires copious amounts of the latter.
Additionally, his Swedish pedigree (which is not yet a requirement for playing in Detroit, but it's getting close to it) make him a comfortable fit in the locker room.
Prior to Mursak's injury, it seemed likely that Brunnstrom was playing his way towards an AHL-contract that would see him start in Grand Rapids, but perhaps be a first-call replacement for the big club.
However, such a contract would have required him to clear waivers which, given his performance thus far, would nearly guarantee him a ticket out of Detroit's system.
Now that Mursak is, quite unfortunately, out of Detroit's plans for the time being, securing Brunnstrom via a two-way, or even a one-way contract is a development that seems now, squarely, in Brunnstrom's hands.
Given how well those hands have performed on the ice thus far, my guess is Brunnstrom won't be leaving Detroit any time soon.
Having depth in the playoffs is essential in the NHL, but having depth in training camp can work out pretty well, too.
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