Change the rules, change the game? Offensive tactics in elite men’s water polo from London to Tokyo

The sport of water polo has frequently undergone modifications throughout its history with two major sets of new rules being implemented in the last decade alone. This paper investigates changes in game play at the elite men’s level over this time, comparing tactical decisions and outcomes from the 2012 London with the 2020 Tokyo Olympics. A detailed analysis of over 4000 plays shows that the distribution of offensive tactical choices changed significantly over this eight-year period with 2020 teams more frequently relying on perimeter shooting and less frequently on counterattacks, centre play, and direct shots. Centre play was the only offensive tactic with a significant increase in efficiency rating. At the game level, major foul calling rates decreased with significantly fewer offensive fouls and exclusion fouls on the ball in 2020. A linear model for predicting final score differential based on differences in game statistics found that number of exclusions, exclusion conversion rate, number of counterattacks, penalty shots, and perimeter efficiency rating were all significant predictors of final game outcomes. There were no significant interactions between year and predictors although there was some evidence that perimeter efficiency rating played a more important role in 2020 compared to 2012.