The first defibrillator has been delivered to a junior team in Sheffield after a £50,000 fundraising drive by rugby league star Danny Jones' widow.
Mr Jones died after suffering a cardiac arrest while playing for the Keighley Cougars last May.
His wife Lizzie Jones launched a campaign to get defibrillators into as many grassroots clubs as possible.
Before his death Mrs Jones said she was "oblivious" to the risk posed by heart problems in players.
"I used to think about injuries," she said.
"What if he breaks his leg or what if he collapses off a bad tackle, but never once did I think about his heart."
Mr Jones, a father to twin babies Phoebe and Bobby, died aged 29.
As well as the defibrillator drive, Mrs Jones campaigned for the screening of all professional rugby league players for cardiac problems.
The Rugby Football League introduced compulsory medical checks for all three of its professional and semi-professional leagues this season.
Mrs Jones said she was "proud" that professional players were now being screened, but amateur and junior players also needed protection
"What about the children and what about the teenagers who are at high risk of this disease?" she said.
"These girls and boys are playing rugby every weekend, mostly going out when there's no doctor there. There might be a first-aid trained person there but they should have that equipment.
"I personally would never let Phoebe and Bobby play anywhere now without knowing they have that equipment there."