Abstract

The outbreak of COVID-19 forced Chinese Football Association to adopt a special format for the 2020 Chinese Football Super League (CSL) after 5-month suspension. All 160 matches (decreased from 240) were divided into two stages (round robin; two-legged knockout) and played behind closed doors in two neutral cities (Suzhou and Dalian). The purpose of this study was to investigate the influence of absence of spectators and format change on teams’ winning percentage and match performance. Technical-tactical and event data of all 400 matches during 2019 and 2020 seasons played by 18 teams were collected. A total of 26 performance indicators were extracted and standardized from the original data. The independent t-test results showed that there were statistically significant differences in 13 performance indicators between 2019 season home win and 2020 season win: shot, shot not on target, simple pass, pass, pass accurate, key pass, corner, corner accurate, dribble and take on (p<0.025, absolute ES: 0.28-0.74) for player performance as well as defensive fouls, defensive third foul and yellow cards for referee decision-making (p=0.001, absolute ES: 0.42-0.45). And there were statistically significant differences in 16 performance indicators between 2019 season home not win and 2020 season not win: shot, shot not on target, touch, simple pass, pass, pass accurate, key pass, corner, corner accurate, dribble, defensive duel, penalty shot and clearance for player performance (p<0.04, absolute ES: 0.21-0.93) as well as defensive third foul, defensive foul and yellow card for referee decision-making (p<0.015, absolute ES: 0.29-0.43). The findings implied that the change of match locations and absence of team supporters led to a decrease in teams’ match performance and an increase in referees’ decision. Although top-ranked teams seemed to be unaffected and the low-ranked teams showed an increase in winning percentage, the fairness of such tournament format needs to be reconsidered.

Resumen

El brote de COVID-19 obligó a la Asociación de Fútbol de China a adoptar un formato especial para la Superliga de Fútbol de China (CSL) de 2020 después de una suspensión de 5 meses. Los 160 partidos (disminuidos de 240) se dividieron en dos etapas (round robin; nocaut a dos piernas) y se jugaron a puerta cerrada en dos ciudades neutrales (Suzhou y Dalian). El propósito de este estudio fue investigar la influencia de la ausencia de espectadores y el cambio de formato en el porcentaje de victorias de los equipos y el rendimiento de los partidos. Se recopilaron datos técnico-tácticos y de eventos de los 400 partidos durante las temporadas 2019 y 2020 jugados por 18 equipos. Se extrajeron y estandarizaron un total de 26 indicadores de desempeño a partir de los datos originales. Los resultados de la prueba t independiente mostraron que había diferencias estadísticamente significativas en 13 indicadores de rendimiento entre la victoria en casa de la temporada 2019 y la victoria en la temporada 2020: disparo, disparo fuera del objetivo, pase simple, pase, pase preciso, pase clave, esquina, esquina precisa, regatear y asumir (p<0.025, ES absoluto: 0.28-0.74) por rendimiento del jugador, así como faltas defensivas, tercera falta defensiva y tarjetas amarillas para la toma de decisiones de los árbitros (p=0.001, ES absoluto: 0.42-0.45). Y hubo diferencias estadísticamente significativas en 16 indicadores de rendimiento entre la temporada 2019 en casa no ganar-la temporada 2020 no ganar: disparo, disparo no a puerta, toque, pase simple, pase, pase preciso, pase clave, esquina, esquina precisa, regate, defensiva duelo, lanzamiento de penalti y despeje para la actuación del jugador (p<0.04, ES absoluto: 0.21-0.93) así como tercera falta defensiva, falta defensiva y tarjeta amarilla para la toma de decisiones del árbitro (p<0.015, ES absoluto: -0.29-0.43). Los hallazgos implicaron que el cambio de ubicación de los partidos y la ausencia de seguidores de los equipos llevaron a una disminución en el rendimiento de los partidos de los equipos y a un aumento en la decisión de los árbitros. Aunque los equipos mejor clasificados no parecieron verse afectados y los equipos de clasificación baja mostraron un aumento en el porcentaje de victorias, es necesario reconsiderar la imparcialidad de dicho formato de torneo.

https://doi.org/10.5232/ricyde2022.06801

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soccer; match location; behind closed doors; spectators; home advantage; fútbol; ubicación del partido; a puerta cerrada; público; ventaja de jugar en casa.