A red card is one of the most significant events that can impact the outcome of a soccer game. This article examines the importance of bookings (both red and yellow), how they affect game probabilities, how managers adjust and why they place away teams at a disadvantage.Read now to understand how bookings affect live soccer betting.
The red card: a soccer game changer
While everyone understands the circumstantial effect of red cards – the immediate loss of a player –statistical analysis helps us better understand the extent to which teams are negatively impacted when they receive a red card.
Unsurprisingly, the team that had a player sent off gained fewer points per game. Over the 60 Premier League games where a team saw a red card in 2012, 20% dropped points at the final whistle when compared to their predicted points (based on the score prior to sending off).
For the 20 teams that were drawing at the time of receiving a red card in last seasons Premier League,65%went on to lose, 30% held on for a draw and just 5% –one team – managed to win.
The negative impact of a red card on a team is also evident in the amount of goals they score and concede. A study by Titman et al. (2012) highlighted that teams playing against a red-carded rival benefited by a 64.5% scoring rate increase.
Previous research looking at a number of Premier League seasons also indicates that the longer teams have a player deficit, the worse off they will be. If a team receives a red card in the first minute, their average goal difference in the game would be reduced by about 1.5 goals. This is reduced to 0.85 and 0.62 if a team is effected by a red card at half-time and 60 minutes respectively.
These figures can enable live bettors to gauge whether live odds have accurately changed to reflect red card incidents, and potentially to measure the significance of yellow cards, the most common precursor to a red.
Don’t underestimate the importance of yellow cards
With the knowledge that red cards can dramatically change the expected course of a match, and given a yellow card can lead to a red, bettors should understand the importance of a yellow card as more than a pause in play.
As yellow cards increase during a game, the in-play probability of a player being dismissed grows. Titman et al. (2012) stated a yellow card to any player on a team in the Premier League more than doubles the hazard of a straight red card to any other player on that team.
Interestingly, Titman also discovered that a team’s booking rate increases by 25% if the opposing team receives a yellow card, which reinforces the notion that referees have a tendency to ‘even up’ decisions during the game.