Facing the challenge of COVID-19 has been front and centre in the news for years. Even in the world of hockey, the virus has been inescapable, with empty arenas, safety protocols, and most notably game postponements, becoming a part of our everyday life.
These postponements have affected everyone, and have been discussed extensively. Every team faces their own challenges, with games intended to be played earlier in the season being tacked on down the stretch, creating exhausting patches of schedule like the one the Flames recently experienced, playing five times in seven nights.
Unlike the NBA, there is little to no load management in the NHL—the practice of resting top players in some games to have them at their best in others. Players are regularly asked to play over 20 minutes a night, all season long. What effect this has on performance is obvious. Tired players will naturally play worse, at any sport.
In the Flames’ recent stretch, this was apparent. While no one could fault their effort, it was clear the team was playing tired against Colorado, the final game of the five in seven stretch. Something that was noticeable that night however, was that Brett Ritchie seemed on top of his game.
Although the ceiling for Ritchie’s game is not high, he had a noticeable jump in his step, bringing much needed energy to the group. It was also his first game in over a week.
This got me wondering in more detail about the impact of tired players on team performance.
Measuring the fatigue factor
To roughly estimate the performance of the team while tired, I separated their stats from games played on the second night of back to backs from their season total. At the team level, the impact of playing back-to-back is almost exactly what you would expect. The stats below are 5v5, score- and venue-adjusted from Evolving-Hockey.com.
|Metric||Back-to-Backs||All Other Games||% Change|
Possession, chance creation, and goal share are worse, as you would expect from a tired group. But the breakdown of their component parts tells an interesting story. Expected goals for actually increase, along with Corsi for, suggesting that the offence is less impacted than the defence by a busy schedule.
But, on the defensive side of things, expected goals and Corsi against increase by an even greater margin. The overall outcome is a weaker team, with only a 53 percent goal share, as opposed to 59 in non back-to-backs.
This makes some sense. Being tired leads to defensive breakdowns, which leads to the need to push more for offence, which once again weakens defence. On top of that, there are 12 forwards to share the load on back-to-backs, and only half as many defencemen. It could be that defencemen feel the effects of fatigue more than forwards.
At the player level, we can explore this in more detail. Data is again from Evolving-Hockey.com
This table shows the change in each statistic compared to non back-to-back games for each individual player. Sorted from best to worst on the second night of back-to-backs based on expected goals, we can see the impact of fatigue on individual players.
Overall, it seems like the players who play the most, the top line and defensive pairing, do not suffer the most. Most likely, these are players who are used to a heavy workload, and are naturally more equipped to play tired.
At the end of the table, bottom of the roster players are most affected by fatigue. Ruzicka, Richardson, Lewis, along with the bottom pair, round out the bottom five. At the other end of the spectrum, Tyler Toffoli and Ritchie lead the way. These two being on top makes a lot of sense.
Ritchie has played in 30 games, and Toffoli 52 (although this data in specific only includes his time with Calgary). Almost everyone else—with the exception of Brad Richardson—has played in 60 games, as the Flames have enjoyed remarkable health as a team. That’s not to say Toffoli’s time hurt with the Montreal Canadiens was a vacation by any means, but it’s possible that playing fewer games has helped him remain slightly fresher.
Getting the most out of back-to-backs
Overall, the data isn’t exactly mind-blowing. The players in the middle of the table are essentially the same regardless of whether or not they play a back-to-back, and there is limited evidence to suggest plugging in a scratch for energy is worthwhile. Despite Ritchie’s strong underlying numbers, he’s just one man, and it could be a coincidence based on the small sample that he is so strong on the second night of back-to-backs.
On the other hand, the other fourth line talents that Darryl Sutter relies on more regularly are at the opposite end of the spectrum. It would be an interesting experiment to more regularly sub in rested players into the bottom-six, and see the impact on back-to-back performance.
As far as load management goes, the data does show that the Flames are worse on the second night. Sutter’s philosophy of rolling four lines likely mitigates this fatigue effect already, but taking a look at this data provides valuable insight for lineup decisions, especially at the bottom of the roster.
With five back-to-backs remaining, Sutter and his staff will need to get the most out of the team. Hopefully his patented brand of fast-paced line-rolling hockey can get the job done.
Ahead of tonight’s contest, the bookies have predicted a double favourite, with Betway Sports pricing the Calgary Flames at +110 and the Vancouver Canucks at +155 to win the game in regulation, with an overtime decision being priced at +330.