“…Previously, lots of studies focusing in football performance analysis had used different sources of data, mainly included Prozone Sports Ltd ® (Valter et al, 2006;Bradley et al, 2007;Bradley et al, 2011), Gecasport (Gómez et al, 2009a;2009b;Lago-Peñas et al, 2010), Amisco Pro ® (Di Salvo et al, 2007;Carling et al, 2008;Dellal et al, 2011) and OPTA Sportsdata (Oberstone, 2009;2011). The accuracy and reliability of former three data resources have already been verified, while the data from OPTA Sportsdata has still not been validated.…”