Medical emergencies in the crowd caused two Premier League matches to be halted on Wednesday night.
The game between Watford and leaders Chelsea was stopped for more than 30 minutes after a supporter suffered a cardiac arrest during the first half.
The fan was stabilised before being taken to hospital.
Later, the start of the second half between Southampton and Leicester was delayed after a supporter was taken ill.
At Vicarage Road, the incident happened as Watford defender Adam Masina was receiving treatment.
Medical staff from both teams raced across the pitch to deal with the emergency, as both sets of players returned to the dressing rooms in the 12th minute with the score 0-0.
Almost 25 minutes after the game was halted, the supporter was carried out on a stretcher and the game resumed 32 minutes after it was stopped.
"Our thoughts are with the fan - who had a cardiac arrest but has now been stabilised - and all those affected," said Watford.
"Thank you to the medical staff, players and fans for their quick response."
Chelsea said: "The thoughts of everyone at Chelsea Football Club are with the fan and all those affected. Our thanks to the medical staff here at Vicarage Road for their quick response."
In October, Newcastle fan Alan George Smith collapsed during the team's Premier League home defeat by Tottenham.