51.95% — the Flyers’ Expected Goals For percentage (xGF%) in the third period this season when leading by one or two goals.
(Programming note: “Expected Goals” are the percentage of goals scored during the game that one would expect a team to collect based on the volume and quality of the shots they take and allow. For more specifics on the particular model of Expected Goals referenced in this post, courtesy of Moneypuck, click here.)
Much has been made of the Flyers’ play by period of the game this season. Their first-period struggles have been an issue for basically the entire year, while their strong third periods have also been a pretty steady occurrence. You’ve probably seen the below numbers pop up on the screen on a recent NBC Sports Philly broadcast, but just in case you haven’t:
Flyers Goal Differential By Period:
1st: Minus-10 (56-66)
2nd: Plus-9 (65-56)
3rd: Plus-23 (79-56)
One thing that they’ve managed to do to maintain that type of an edge? They’ve kept their foot down when trying to hold a lead in the third. You could have seen that in action on Tuesday night, when the Flyers entered the third period with a 3-1 lead and managed to stifle any real comeback attempts from San Jose, outshooting them 9-3 in the process. But performances like that are becoming the norm for them.
There’s a phenomenon in hockey known as score effects — the idea that, when a team is leading in a game, the trailing team tends to get more shots and scoring chances. This tends to be most pronounced in the third period, which makes sense; at that point of the game, one would imagine, one team knows it’s running out of time to tie the game up and really ramps up the urgency to go all-out while the other team knows it needs to avoid making a big mistake that may lead to a tie game.
With that said, recent work done by Micah Blake McCurdy of HockeyViz has suggested that score effects are driven more by the leading team sitting back than they are the trailing team pushing forward. In other words, when a team that’s trailing late in the game ends up mounting a big push late, it typically has more to do with the leading team doing less than it does the trailing team doing more.
Which brings us to our Philadelphia Flyers, who have made an earnest attempt to do more when holding those leads. If we isolate this to look at each team’s performance in the third period while leading by one or two goals (i.e. times when a game is realistically still within reach), the Flyers’ aforementioned 51.95% Expected Goals For rate is the sixth-best in the NHL.
For fun, let’s compare that number to the Flyers’ normal 5-on-5 Expected Goals rate. We’ll call the difference between those two numbers the “Shell Effect”, in honor of the “defensive shell” a team can go into while it’s trying to hold a lead. Turns out, the Flyers’ numbers in these situations where they’re holding a close lead late are actually better than their normal 5-on-5 numbers, and the difference between those two numbers for them is the fifth-best in the NHL. (The below table is sortable.)
5-on-5 Expected Goals, 3rd Period, Leading by 1-2 Goals
| Team | xG For | xG Against | xG For % | xG % (All 5-on-5) | Shell Effect |
|---|---|---|---|---|---|
| CHI | 9.29 | 9.38 | 49.75% | 46.42% | -3.33% |
| N.J | 10.23 | 10.19 | 50.08% | 46.85% | -3.23% |
| MTL | 12.12 | 9.17 | 56.95% | 53.82% | -3.13% |
| BOS | 14.59 | 12.39 | 54.08% | 51.98% | -2.10% |
| PHI | 12.43 | 11.5 | 51.95% | 50.45% | -1.50% |
| DAL | 12.9 | 11.17 | 53.59% | 52.33% | -1.26% |
| EDM | 9.98 | 9.8 | 50.45% | 49.25% | -1.20% |
| NYR | 11.08 | 12.21 | 47.58% | 46.60% | -0.98% |
| FLA | 8.93 | 9.37 | 48.80% | 48.23% | -0.57% |
| NSH | 10.1 | 9.55 | 51.40% | 50.96% | -0.44% |
| T.B | 12.32 | 10.45 | 54.10% | 54.30% | 0.20% |
| TOR | 12.52 | 12.15 | 50.76% | 51.32% | 0.56% |
| CAR | 8.58 | 7.82 | 52.32% | 53.14% | 0.82% |
| CBJ | 7.99 | 8.02 | 49.90% | 51.67% | 1.77% |
| ARI | 10.72 | 12.54 | 46.07% | 49.54% | 3.47% |
| OTT | 8.7 | 10.58 | 45.12% | 48.91% | 3.79% |
| CGY | 11.16 | 12.54 | 47.09% | 50.95% | 3.86% |
| BUF | 7.27 | 9.19 | 44.18% | 48.40% | 4.22% |
| NYI | 11.64 | 14.07 | 45.27% | 49.63% | 4.36% |
| S.J | 6.81 | 8.83 | 43.55% | 48.39% | 4.84% |
| STL | 13.09 | 15.73 | 45.42% | 50.54% | 5.12% |
| ANA | 7.18 | 9.82 | 42.23% | 47.43% | 5.20% |
| WPG | 5.9 | 9.89 | 37.36% | 43.34% | 5.98% |
| WSH | 12.66 | 17.26 | 42.31% | 50.00% | 7.69% |
| MIN | 10.09 | 12.75 | 44.16% | 53.14% | 8.98% |
| L.A | 6.14 | 7.99 | 43.46% | 52.45% | 8.99% |
| VAN | 8.61 | 13.84 | 38.36% | 48.21% | 9.85% |
| COL | 10.18 | 15.29 | 39.99% | 50.45% | 10.46% |
| PIT | 7.41 | 10.51 | 41.34% | 51.85% | 10.51% |
| VGK | 10.89 | 14.04 | 43.69% | 54.81% | 11.12% |
| DET | 2.79 | 7.29 | 27.68% | 44.65% | 16.97% |
Again, this is the side of score effects that is more team-driven. The fact that they’ve managed to keep the pedal down here and get the better of the flow of the game in situations that are typically dictated by the opposing team is a great sign. And it’s a sign of improvement, too — in each of the last two seasons, the Flyers were about five percentage points of xGF% worse in these situations than they were in total, as opposed to the one-and-a-half points better that they are this year.
There are certainly small sample considerations that have to be taken into account here — this is about a handful of full games’ worth of hockey, a short enough period of time that crazy things can happen. And the Flyers’ numbers while holding a 1-2 goal lead across the whole game are just-OK (49.5 xGF%, to be precise), which underscores the need to play well early in games. But it’s encouraging to see that when they need to close the deal late, they’ve been playing the right way.
Now if they could just figure out the damn first period.
