Bye - Gift or Curse?

I touched on this topic in my last post, and it's not a new idea, but in sports where teams performing well in the regular season are rewarded with a bye, is this more of a curse than a gift? 

The argument is that teams become rusty whereas their opponents do not lose, and arguably gain, momentum by coming through that extra round or series.

The play-off format for MLB this season is new, but the Wild Card round has been around since 2012, though not in 2020 when COVID rule changes resulted in a 16 team play-off field with no byes.

From 2012 to 2021 (9 seasons excluding 2020) each League had one Wild Card game with the winner advancing to play the team with the best Regular Season record, so the number of extra rest days for the top seed was minimal.

Nevertheless, of the 18 series between the Wild Card game winner and the number one seed, the Wild Card team advanced 50% of the time, while winning 43% of individual games.  

The format this season changed with the addition of an extra Wild Card Team in each League, and instead of a single elimination game, the Wild Card Series games are now a best-of-three series, meaning the resting teams (now the number one and number two seeds) have a longer rest.

So the data for one season is obviously very limited value, but both the #1 Los Angeles Dodgers and #2 Atlanta Braves lost their series in the National League, while in the American League the #1 Houston Astros swept their series, and the #2 New York Yankees are tied at 2:2.

With the additional days of rest, and the ability of the top seeded team to have their best starting pitcher available, it's perhaps not too surprising that in the opening game of a Rested v Wild Card team, the Rested team prevails in 75% of Game 1 fixtures, before the rust settles in. After this, the ROI on backing the Wild Card team is a solid 18.8% since 2016. Unfortunately for 2012 to 2015 the Killer Sports data is incomplete. 

Another major sport that rewards its top regular season performers with a bye week is the NFL, and here the data since 2002 shows that the rested team underperforms with just a 36.4% record ATS. 

Something to think about in the New Year when the NFL Playoffs begin.