Dec 16 (Reuters) - The ATP Tour said it will introduce a new heat policy that will come into effect from 2026 after a string of retirements due to soaring temperatures and punishing humidity at the Shanghai Masters earlier this season.

The governing body of men's tennis said the rule, based on the internationally recognised Wet Bulb Globe Temperature (WBGT) index used to measure human heat stress in direct sunlight, had "clear thresholds" for cooling measures and suspension of play.