Two of the Closest Series Ever

Last night's overtime victory by Washington completed what was likely the closest series in NHL history in terms of score.  Not only was every game decided by a single goal, but 99.4% of the entire series was played with a goal differential of one or less.  The only time either team managed to take a two goal lead over the seven games was when Jay Beagle scored in the second period of game five to put the Caps up 2-0, a margin that lasted less than three minutes before the Bruins cut it to 2-1.

The West had a matchup that was also a strong contender for the title of closest ever right up until the final period of the series.  Phoenix and Chicago went to overtime in each of the first five games of the series, and by the time of the second intermission in game six had spent 99.3% of their series tied or with one of the teams leading by a lone goal.  However, in that final period Phoenix finally broke through and pulled away for a decisive 4-0 win.

I thought it would be interesting to look at numbers broken down by score in these two series to see why they were so tight.

Boston vs. Washington:

Washington Up One:
Shots:  Washington 30, Boston 72
Goals:  Washington 1, Boston 7
Save %:  Holtby .903, Thomas .967

Score Tied:
Shots:  Washington 145, Boston 162
Goals:  Washington 11, Boston 7
Save %:  Holtby .957, Thomas .924

Boston Up One:
Shots:  Washington 32, Boston 11
Goals:  Washington 4, Boston 0
Save %:  Holtby 1.000, Thomas .875

There were major score effects during the series, as would be expected.  Including the brief period when Boston was down by 2, the trailing team outshot the team in the lead by the whopping margin of 107-41 and scored 12 goals in just 141.7 minutes of play for an amazing rate of 5.08 goals per 60 minutes.  The leading team managed just one goal (0.42 per 60), scoring on just 2.4% of their shots taken.

It is typical that the trailing team generates more shot attempts, but usually their percentages drop as they put more pucks on the net and take more risks, leaving themselves open to chances going back the other way.  For whatever reason both the Caps and Bruins were able to get away with almost everything in their own end when pushing for the tie.

The overall shot statistics flatter the Bruins a bit because they spent more time trailing.  Boston outshot Washington by 20% overall but by just 12% with the game tied.  It was still a very close series, and Washington was pushed over the top by an impressive effort from rookie netminder Braden Holtby.

The Chicago-Phoenix series was similarly close in terms of scores, but the underlying numbers suggest that balance of play wasn't nearly as tight.

Phoenix vs. Chicago:

Phoenix Up Two Goals or More:
Shots:  Phoenix 11, Chicago 11
Goals:  Phoenix 2, Chicago 1
Save %:  Smith .909, Crawford .818

Phoenix Up One:
Shots:  Phoenix 40, Chicago 76
Goals:  Phoenix 2, Chicago 5
Save %:  Smith .934, Crawford .950

Game Tied:
Shots:  Phoenix 73, Chicago 124
Goals:  Phoenix 9, Chicago 6
Save %:  Smith .952, Crawford .877

Chicago Up One:
Shots:  Phoenix 35, Chicago 30
Goals:  Phoenix 4, Chicago 0
Save %:  Smith 1.000, Crawford .886

In this series the Blackhawks outshot the Coyotes by 51% overall, and an impressive 70% with the game tied, yet somehow managed to get outscored 17-12 over the course of six games, as well 9-6 in tie-game situations.  The strong goaltending of Mike Smith compared to the inconsistent play of Corey Crawford was the decisive factor in the series.

Smith was particularly strong in game six, a game where everything was massively tilted in favour of Chicago except for the scoreboard.  I also found it interesting that Smith had the highest save percentage of any of the four goaltenders while his team held a one goal lead, which was perhaps unexpected given that the Blackhawks fought back three times to tie the game late in the third period.  Several posters in this HFBoards thread specifically downgrade Smith's first-round performance because of his supposed lack of clutch play in allowing late game-tying goals, but to me that's making the classic mistake of evaluating playoff performance:  Letting a few memorable events have too much influence while failing to properly appreciate the larger picture.

For the sake of comparison, Braden Holtby gave up a lead in five out of seven games, including twice in the third period, yet nobody would call him unclutch.  Allowing goals against in the final 10 seconds obviously has a huge negative impact on a team's win probability, but when 99% of the series is within one goal then every goal against has a major impact on the chance of victory.  Other than one third period in Chicago, pretty much every situation these four goalies have faced so far in the 2012 playoffs was a clutch situation.

Just as with Washington and Boston, the trailing team rode both a large outshooting advantage and insanely high percentages.  Overall, shots were 122-81 in favour of the team playing catch-up, with turned into a 10-4 advantage on the scoreboard.  That works out to a rate of 3.16 goals per minute for the trailing team, compared to just 1.26 for the team holding on to a lead.

In some respects it is amazing that Chicago even came as close to winning the series as they did, given that Phoenix's scoring rate per shot was over twice as high.  The repeated late-game comebacks to force OT kept them in it, but unfortunately the goaltending disparity was perhaps never more apparent than in extra time where Smith managed a .923 save percentage while Crawford put up a mere .813 and let in two very soft goals to help the Coyotes to the franchise's first second round appearance since 1987.

It would be interesting to see detailed scoring chance numbers or a breakdown of odd-man rush chances to see whether the leading teams were generating chances and just missing their shots, or whether their defensive focus meant they were not creating many dangerous opportunities to score.  In the absence of compelling evidence, however, I'd guess it was mainly a tremendous run of hot goaltending that kept the scores close (in both series combined, goalies on teams trailing by one stopped 97.3% of the shots against) and created 13 games of razor-thin margins in these two memorable series.