Fortunately, subsequent tests determined Kante did not have a heart problem.
Kante travelled with the Chelsea squad to Manchester for Sunday's match but was rested after he said he was feeling unwell.
His team-mates were understandably concerned and were apparently anxious Kante may have had a previously undiagnosed heart issue.
It's now been revealed the France worldwide fainted at the club's training ground on Friday during a routine session and after an assessment from the medical team, it was decided the 26-year-old would not be risked against the Citizens.
But, as noted by Law, Kante's incident has been "brought into sharp focus" after the sudden death of Fiorentina captain and Italy global Davide Astori on Sunday due to a "sudden illness".
A Chelsea doctor is thought to have arrived at the ex-Leicester star's aid after he slumped to one side in the Cobham dressing room. The Telegraph earlier reported Kante's health scare on Monday.
It is not known why Kante fainted, but last week's freezing temperatures are thought to have been a contributing factor.
A specialist cleared Kante to play in the match, and the 26-year-old is available for selection for this weekend's game against Crystal Palace.