The aim of this study was to assess the extent to which measures derived from the new FIFA referees' fitness tests can be used to monitor a referee's match-related physical capacity. Match-analysis data were collected (Prozone, Leeds, UK) from 17 soccer referees for 5.0 (s = 1.7) FA Premier League matches per referee during the first 4 months of the 2007-08 season. Physical match performance categories included total distance covered, high-intensity running distance (speed >5.5 m x s(-1)), and sprinting distance (>7.0 m x s(-1)). The two tests were a 6 x 40-m sprint test and a 150-m interval test. Heart rate demand was correlated with total match distance covered (r = -0.70, P = 0.002) and high-intensity running (r = -0.57, P = 0.018) in the interval test. The fastest 40-m sprint was related to total distance covered (r = -0.69, P = 0.002), high-intensity running (r = -0.76, P < 0.001), and sprinting distance (r = -0.75, P = 0.001), while mean time for the 40-m sprints was related to total distance covered (r = -0.70, P = 0.002), high-intensity running (r = -0.77, P < 0.001), and sprinting distance (r = -0.77, P < 0.001). The referees who recorded the best interval-test heart rate demand and fastest 40-m time produced the best physical match performances. However, only the sprint test and in particular the fastest 40-m time had appropriate construct validity for the physical assessment of soccer referees.