A football supporter required CPR after falling ill at The New Croft, shortly before the Haverhill derby between Borough and Rovers was due to kick off on Friday night.
The man is understood to have suffered a heart attack and, after being made stable by paramedics, was transferred to Norwich Hospital by the East Anglian Air Ambulance.
The incident began to unfold minutes before both teams were due on the pitch for the town's second ever football derby.
There was a large crowd in attendance at the ground, which is shared by both Borough and Rovers, when it became apparent something was wrong.
A man, believed to be a football supporter at the club to watch the game, had become unwell and fallen to the ground - and Welfare Officer Lisa Shulver and Borough player Tommy Hardwick had immediately gone to his aid.
Shulver is one of the club's first aiders while Hardwick, who was named on the substitute's bench for Borough, is a firefighter with first aid training.
The two worked together to administer life-saving treatment, needing the club's defibrillator, while emergency services were called.
An ambulance and air ambulance arrived very quickly and landed on Rovers' grass pitch.
Paramedics on the scene said that Shulver and Hardwick's quick response probably saved the man's life.
Peter Betts, Haverhill Community Sports Association s football development officer and facilities manager, said: "I'm just so glad we had the defibrillator on site.
"After the Muamba case a few years ago, we applied for funding from the FA to get one here, and it proved worthwhile tonight.
"If it wasn't here, well, he would not still be with us. And also to the two who responded first.
"Lisa and Tommy just really got on with it and I think everyone would like to thank them for their actions.
"Their quick thinking was vital to saving his life.
"Both teams have rallied round and, at the end of the day, there are much more important things than a football game."
The game has been postponed and will, presumably, be rescheduled by the Thurlow Nunn Premier Division soon.
Betts confirmed that there were contingency plans in place and, while unfortunate to have to turn to them, they had provided those in attendance with a ticket to return when the game was rescheduled.