Analysis of Set Piece Plays in High-Level Football: Corners and Indirect Free Kicks. An Attempt to Identify Explanatory Variables
The purpose of this paper is to learn more about two specific types of plays at set pieces which are extremely important in top level football: corners and indirect free kicks. The study analyses the effectiveness of this type of play, identifies the most significant variables leading to success (shot, shot on target and goal) and puts forward a model for successful corners and indirect free kicks.After recording 1139 corners and 783 indirect free kicks taken in the 124 matches analysed in the FIFA World Cup 2010, the UEFA Champions League 2010-2011 knockout stage and UEFA Euro 2012 and carrying out univariate, bivariate and multivariate analysis, the results indicate the low effectiveness of these kinds of plays in terms of shots, shots on target and goals. The most relevant conclusions of both investigations include: 1) The effectiveness of this type of play is very limited since it takes 4 corners and 5 indirect free kicks to produce a shot; 10 and 11 respectively to produce a shot on target; and 50 corners and 36 indirect free kicks to produce a goal; 2) Despite being very low effectiveness plays, 76% and 64% of the goals that come from corners and indirect free kicks respectively enabled teams to win the game or earn points; 3) Unlike the usual way in which teams perform of this type of play using crosses into the area, aerial balls and the involvement only of the player taking the kick and the player who shoots or heads, the empirical results suggest that by contrast the alternative tactics of teams which decide to make this move somewhat more elaborate based on passing the ball around, the involvement of three or four players and dynamic attacking organisation is the best way to score or shoot; 4) Logistic regression has highlighted the key role of three specific variables in the case of corners: attacking organisation, the number of attackers that touch the ball and the area where the shot takes place. As for indirect free kicks, again there are three key variables in the explanatory model, namely attacking organisation, the trajectory of the ball and the number of attackers that touch it.