July 28 (Reuters) - An autographed Patrick Mahomes rookie card printed in 2017 has become the most expensive NFL card after it sold for $4.3 million, breaking the previous record of $3.1 million for a Tom Brady-signed rookie card, PWCC Marketplace said. "We just brokered a record-breaking $4.3 million private sale for a 2017 National Treasures NFL Shield Patrick Mahomes Rookie Auto 1/1 to LJ’s Card Shop," PWCC tweeted. "This is the highest price ever paid for a football card!" Kansas City Chiefs quarterback Mahomes was voted the NFL"s Most Valuable Player (MVP) in 2018 and then helped guide the Chiefs to Super Bowl victory in 2020. Last month, a signed card from Brady"s rookie season with the New England Patriots sold for $3.107 million at the Lelands Mid-Spring Classic auction. read more