To reschedule or not to reschedule, that is the question

To reschedule or not to reschedule? That is the question on the minds of many Big Ten and specifically Michigan State University basketball fans this week. On Saturday, the Spartans were planning to face the Michigan Wolverines in Ann Arbor in the first of two scheduled games this year. However, the game was officially postponed just hours before tip-off due to COVID-19 protocols in the Michigan program.

In an ideal world, there would be enough time and flexibility in the Big Ten conference schedule to allow for the game to be rescheduled sometime later this year. Unfortunately, the current 20-game conference slate will make it difficult to find a date where one or both teams is not forced to play three or four games in an eight- or nine-day span, similar to what Michigan State went through at the end of the 2021 season.

Based on Coach Izzo's comments on Monday, Michigan State seems unlikely to support this option.

“I’m not in the mood to do what we did last year where we played four games in eight days against Top 5 teams,” Izzo said. “I’m not sure that’s fair, either.”

Also on Monday, reporter Graham Couch of the Lansing State Journal made a compelling argument that MSU should not reschedule the game in Ann Arbor.

"The Spartans don’t need this game," Couch wrote. "It’s not their home game against Michigan. MSU’s resume thus far is plenty strong, with plenty of opportunities ahead to prove their mettle before the brackets. If they do well against Illinois and Purdue and such and wind up on top of the Big Ten standings, the title will have been well earned, even if they haven’t played the full 20 games."

For me, this situation begs a slightly different question. Can we actually quantify the impact of rescheduling the game or not? Fortunately, we have mathematical tools to do just that.

Throughout this season, I have been calculating the odds for each Big Ten team to win or share the regular season conference title. I use efficiency margin data from Ken Pomeroy to project future point spreads and win probabilities. I most recently ran these number on Monday based on the Big Ten results over the weekend. For these calculations, I assume that the Michigan / Michigan State game as well as the now postponed Michigan / Purdue game would eventually be rescheduled.

On Tuesday, I re-ran the simulation with the exact same input parameters, but with both the Michigan / Michigan State game and the Michigan / Purdue game removed from the schedule (i.e. assuming that they will NOT be rescheduled). The results of this simulation is shown below in Table 1.

Table 1: Updated odds for each Big Ten team to at least share the regular season title as of Jan. 11. The change in parenthesis is the change relative to the full schedule assuming the postponed games are rescheduled.

The results are rather surprising. Based on Table 1, it appears that the odds for all Big Ten go down slightly if these two games are not rescheduled. For Michigan State, the odds drop by about four percentage points, from 24 percent down to 20 percent. Interestingly, Illinois' odds drop by almost the same amount: four percentage points.

As for the other current contenders, Purdue is the team that seems to suffer the most, but the Boilermakers' odds drop by only six percentage points. Meanwhile, the odds for Ohio State and Wisconsin drop by just around two percentage points.

As for the other Big Ten teams, their odds also drop, but by less than a percentage point. But, considering these teams generally have very long odds anyway, this is somewhat significant. As for the Wolverines, their odds would drop to below one percent if those games are not rescheduled.

The reason that these odds all drop is that when the schedule becomes unbalanced and certain teams are playing a different number of games, the chances of a tie decreases. If MSU only plays 19 games and Illinois, Ohio State, and Wisconsin all play 20 games, there is no way for the Spartans to tie any of those three teams for a regular season title.

For example, if Illinois finishes the season at 15-5 (0.750), Michigan State could win the regular season title with a 15-4 (0.789) record. In this case, not playing Michigan does not benefit Michigan State, but it could hurt the Illini. Conversely, however, if the Spartan were to finish with a 14-5 (0.737) record, not having the 20th game on the schedule could cost MSU the title. In both scenarios, at least one team's odds are decreased due to the unbalanced schedule.

As for the relative impact to each team, I believe that can be explained primarily due to the strength of each teams remaining schedule, which is shown below in Figure 1.

Figure 1: Updated strength of each Big Ten team's remaining schedules assuming the postponed games are not rescheduled.

Michigan State and Illinois both have the same number of losses and each teams remaining strength of schedule is similar. Therefore, both teams will suffer a similar impact if those two games are not rescheduled. 

As for Wisconsin and Ohio Sate, Figure 1 shows that the Badgers and Buckeyes have two of the easiest remaining schedules in the conference. Therefore, they each have more of a cushion. As for Purdue, the Boilermakers are already two games back and thus they need all the wins that they can get to climb back into contention.

Based on this analysis, the bottom line is that an unbalanced schedule is essentially bad for the entire conference. However, the quantitative impact is just a few percentage points. 

From Michigan State's point of view, failing the reschedule the game at Michigan does decrease the Spartans' chances to win a regular season Big Ten title. There are scenarios that could happen where an additional win over Michigan would be needed to hang another banner in the rafters at the Breslin Center. If MSU were to lose the rescheduled game, the end result is still the same. From this point of view, rescheduling the game is low risk and high reward.

However, this analysis does not take into account the additional strain that Michigan State would need to endure in order make this game happen. Based on last year's experience, Coach Izzo does not seem think that it is worth it. I would tend to defer to his judgment.

I suppose the question then is whether it is nobler of mind to suffer the slings and arrows of playing that extra game for perchance the dream of another Big Ten Championship? Or, is this simply taking arms against a sea of troubles. Aye, there's the rub.

In any event, Michigan State is still undefeated and fully in charge of their own destiny in the Big Ten race. Yes, there are scenarios where failing to reschedule the game at Michigan could cost the Spartans, but those odds are relatively small. The future, as always, remains the the undiscovered country.