The midfielder dropped to the ground at the Parken Stadium in Copenhagen shortly before half-time, leaving players from both teams in clear distress.
Cameras showed medics desperately trying to stabilise the former Tottenham player, as his teammates formed a protective circle around where he lay on the pitch.
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The event - which took place on Queens Park, Pudsey - was a huge success.
First aid trainer Janice Whitehead and her team talked the coaches through CPR and how to access one of the 21 defibrillators across Pudsey, Swinnow and Tyersal and how to use it, Cllr Seary said.
The session lasted around an hour and at least a dozen coaches were given refresher training.
Many Pudsey residents praised the quick-thinking councillor's decision to host the training.