I have long been fascinated by the evolution of sports records. On the individual sports level they are gradually but inexorably chipped away from one generation to the next. The 100-metre sprint is a classic example (on the men's side, that is; the less said about FloJo the better). When I was born Jesse Owens held the world record at 10.2 seconds, a time which wouldn't get him through a round of heats in a modern Olympics, if indeed he qualified for the Games. Far more impressive is the fact that Owens' magnificent sprint stood against all comers as the world record for 20 long years. Whereas in the last 20, the standard has been improved no fewer than 10 times and by 6 different men. Typically these incremental improvements are by razor thin margins representing very gradual advances in human physiology, kinesiology, training and technique across the field of elite sprinters; only the current holder, Usain Bolt, has carved such a significant chunk off the previous mark -- 1/6 of a second, a positively Beamonesque leap -- to stake a claim as a "generational talent" in the class of Owens. I won't be surprised to see the name Bolt atop that particular list for a number of years; his time was ahead of its time, but ultimately it surely represents just a little jitter in the long term improvement curve.

Team sports are a much more complex beast. Rather than a collective effort against a clock or a measuring stick, there is competition between athletes with one group trying to help one another while working together to prevent the other group from succeeding. Moreover, there are constantly shifting trends and strategies, tweaks to the rule book, and an ever-levelling playing field in terms of athletic talent as the stakes grow higher. Some records become not so much unbreakable as they do obsolete due to fundamental changes in the evolution of the sport. Take for example my other favourite sport, baseball, in which a record like Cy Young's 511 wins has become ever further beyond reach with the passing of the decades. Today's starting pitchers throw much more infrequently -- typically every 5th day -- and are often replaced by relief specialists before a game is decided. 20-game winners are a rarity these days (there were none in 2009). Cy Young won as many as 36 games in a season, and 12 times recorded at least 25 wins. He dominated his own generation, and subsequent ones haven't had a snowball's chance against his statistical legacy. 749 complete games? I don't think so.

Sometimes, though, a sport fluctuates around a rough balance point, "breathing" in and out as first offence, then defence hold sway. In baseball Babe Ruth's career home run record seemed untouchable for decades before Hank Aaron toppled it; the new mark seemed unassailable for decades more before it too fell to Barry Bonds. These men were not just generational talents, but in the right generation.

So it is with hockey. In its 92-year history the NHL has seen three distinct peaks in scoring where goal totals approached and briefly exceeded 4.0 goals per team-game. These have been offset by three valleys, each a couple of decades in duration, where scoring has dropped well below 3.0 G/G. These variations have had a profound impact on the record book. One such category is career shutouts, a major goaltending record which was equalled earlier this week.

Scoring was at its most volatile at the birth of the NHL. In the first NHL season in 1917-18 just 2 shutouts were recorded, 1 each by Clint Benedict and Georges Vezina. Teams scored close to 5 goals per game at the beginning of the 1920s, but this number dropped precipitously over that decade, crashing to fewer than 1.5 goals per game by 1928-29. George Hainsworth of the Montreal Canadiens found himself in the perfect storm that season, recording no fewer than 22 shutouts, a mark that has never seriously been approached even in modern seasons of nearly double the length. His 0.92 GAA of that season has also survived for eight decades; both marks presumably will stay on the books forever.

Those Habs were the most defensive-minded team in a defence-first era. They got shut out 6 times in 1928-29, and never lost a one of them: six 0-0 ties when even "overtime solved nothing" as the talking heads are wont to say. Hainsworth backstopped nine 1-0 wins, while 7 other affairs ended 1-1. That's 22 games -- half the schedule! -- in which the Habs scored one goal or less and still got at least a point. Soccer anyone?

The next season the NHL changed the rules to allow forward passing, and scoring returned. When goal sucking became an issue, the offside rule was introduced midway in the 1929-30 season, which explains the (first) sharp spike in the graph. A second rule change had been needed to moderate the first, and between them some semblance of balance was restored, although the game remained fairly low scoring right into the war years. Still, Hainsworth's totals dropped from 49 shutouts in his first 3 NHL seasons to "just" 45 in his next 7. Soon he had toppled the career marks of early shutout kings Clint Benedict and Alec Connell. Hainsworth retired in 1937 after a 10-year NHL career that saw him record 94 shutouts in just 461 games, less than 5 GP per shutout. It's also worth mentioning that Hainsworth had racked up 10 shutouts in the old Western Hockey League in the years before the NHL took full control of the Stanley Cup, thus technically he still holds the "major league" shutout record of 104, one ahead of the two men who currently share the NHL record and the headlines.

The first of these, Terry Sawchuk, came to the NHL in 1950, just in time for the next goal-scoring drought. Scoring had surged in the 1940s and peaked during the height of World War II. By Sawchuk's arrival, post-war scoring had dropped to about 2.7 G/G and would bottom out around 2.4 early in his career. During that defence-first era Sawchuk played on the best defensive team in the NHL, the Detroit Red Wings, maintaining a GAA below 2.00 for 5 years running and racking up shutouts galore in the process. At the end of his sixth NHL season Sawchuk already had 66 shutouts in the books and Hainsworth's mark was clearly in jeopardy. In subsequent years as NHL scoring rebounded again and Sawchuk's own skills waned, he made slower but steady progress, finally toppling Hainsworth's career mark 8 seasons and 29 shutouts later. Sawchuk became the first goalie to reach 100 NHL shutouts just before expansion changed the game forever, and when he died in 1970 his career mark of 103 clean sheets seemed secure. He had also played a record 971 games, just under 10 GP per shutout. The two-goalie system held sway and both records looked rock solid.

As the expansion era took hold, scoring ratcheted upward throughout the 70s and into the 80s, where it once again peaked above 4.0 G/G, remaining above 3.7 throughout the decade. Shutouts became rare birds indeed; after Tony Esposito retired in 1984, no active goaltender reached as many as 30 career shutouts until 1996. The two-goalie system was no longer in vogue, so Sawchuk's GP record came under attack and would eventually be surpassed by Patrick Roy. Still, that shutout record looked like Mount Everest.

When Gary Bettman became NHL Commissioner in 1993 goal scoring was a respectable 3.63 G/G. The next wave of expansion was just underway, only this time it had the opposite effect, as new teams found it easier to prevent goals than to actually score any themselves. Parity was encouraged in not-so-subtle ways, including lax rules enforcement of obstruction penalties. Hockey's new fans from the football country of the deep south seemed to accept blocking and tackling as part of the game. Within 5 years of the Bettman regime, NHL scoring had plummeted by a full goal per game for each team, and despite various attempts to kick-start offence in recent years, the Dead Puck Era has persisted from the mid-90s right through the oughts.

The timing couldn't have been better for Martin Brodeur, who like Bettman joined the NHL in 1993. He has played in one organization throughout his career, the New Jersey Devils, probably the NHL's best defensive team in a defence-first era -- spot the trend? -- and certainly a club ideally suited for a man of Brodeur's considerable skill-set. Among his many talents is longevity: earlier this season MB30 set the NHL record for minutes played, and in the next week or so will topple Patrick Roy's mark for GP by a goaltender. After a slow start (during the highest-scoring years of his career) he has racked up shutouts at a very steady rate of about one for every 10 GP; indeed at this writing he stands at 1028 GP and 103 SO.

The list of the NHL's top 10 career shutouts leaders currently features exactly three goalies from each of hockey's three low-scoring eras, with a lone outsider creeping on to the very bottom of the list. Listed career spans exclude "cups of coffee" seasons of fewer than 10 GP.

(Stats courtesy Hockey-reference.com)

Each of the low-scoring eras had good competition but featured a clearcut shutout champion. Whether he was the best goalie of the day, played on the best team, or had a career that was best centred on his low-scoring era is open to discussion. I will return to this matter with another methodology in the coming days.