Flutter’s owner has suffered a huge loss to NFL fans.

Flutter, the owner of US-listed Fanduel, has warned that its profits and revenues will take a hit after customers get more chances to win on US sporting events.

The company said in a business update on Tuesday that the NFL season is the most “customer-friendly” since the launch of online sports betting, with the highest popularity in 20 years.

Flutter said his biggest one-time loss of the quarter was the $74 million cost of the Detroit Lions’ Dec. 30 win over the San Francisco 49ers.

Flutter said it will take in about $390mn in revenue from November 12 to December 31.