“…The limitations of the human visual system to process the information in these complex situations is an additional source of incorrect offside judgments (Baldo, Ranvaud, & Morya, 2002;Belda Maruenda, 2004;Gilis, Helsen, Catteeuw, & Wagemans, 2008;Helsen et al, 2006). For instance, on and off the field training sessions that are in line with the physical and perceptual-cognitive demands of the game should be implemented for top-class assistant referees to reduce the number incorrect offside decisions (Catteeuw, Gilis, Wagemans, & Helsen, 2010c;Catteeuw, Gilis, Jaspers, Wagemans, & Helsen, 2010d;Catteeuw, Helsen, Gilis, Van Roie, & Wagemans, 2009b;Gilis, Helsen, Catteeuw, Van Roie & Wagemans, 2009). Given the high accuracy presented by both referees and assistant referees when judging the play, we suggest that their technical performance should be expressed in the future as a percentage of successful decisions instead of relating it to the number of errors.…”