Uzbek official Ilgiz Tantashev, a FIFA referee widely criticised for his handling of France’s last-16 win over Paraguay, was reportedly experiencing extreme heat strain during the match. New data from wearable tech maker Core indicates that Tantashev's core temperature reached 39.3C, with his Heat Strain Index (HSI) score hitting 6.7/10 for the fixture.
L'Equipe gave Tantashev a 1/10 rating, and BBC pundit Thomas Hitzlsperger called it “the worst performance I’ve seen so far at this tournament”. Academic research suggests that such levels of heat strain are associated with impaired decision-making, reduced reaction time, and can affect perception, attention, and anticipation.
Core chief commercial officer Ross McGraw stated that the referee’s HSI climbed to a level linked in published research with these issues. The data also indicated that climatic conditions, rather than distance covered, were the primary driver of heat strain, with the France v Paraguay game played in 34C heat at 5pm.