Conditions at the US Open were described as “dangerous” as five men had to retire from their first-round matches on Tuesday because of heat-related issues. Temperatures close to 38C (100F) in New York were made more stifling by humidity levels…

Conditions at the US Open were described as “dangerous” as five men had to retire from their first-round matches on Tuesday because of heat-related issues. Temperatures close to 38C (100F) in New York were made more stifling by humidity levels…