OSKAR GARCIAYahoo Sports is apologizing for a site outage that left thousands of fantasy football players complaining of last-minute lineup problems and possible lost money on an NFL Sunday. Ken Fuchs, head of entertainment, sports and games at Yahoo Inc., emailed players early Monday to apologize for problems with the site and its mobile apps. "I'm disappointed that we failed all of our fans today," Fuchs wrote in the email. "Our first priority is having the best experience for our users, and today we fell short." Fuchs said the outage started about one hour before the first games kicked off, which he called "awful timing." Yahoo, along with sites run by ESPN and CBS Sports, is one of the biggest players in the $800 million-per-year fantasy sports industry, hosting leagues where users pick a team of real-life players and compete based on their individual statistics. A study last year found that 32 million people in the United States and Canada were playing fantasy sports, according to the Fantasy Sports Trade Association. Football is by far the most popular fantasy sport. Many players play casual leagues just for fun, but others gamble money â¿¿ sometimes big money. Yahoo said Monday afternoon on its fantasy football Twitter account that the website was back up, but users were still unable to make lineup changes on mobile apps. Players enraged about the outage took to Twitter, Facebook and Reddit on Sunday and Monday to express their displeasure, some saying they planned to switch platforms as a result. "I feel like I lost out a lot," said Bryan Smothers, a 27-year-old small business owner from Eureka, Calif., who said the site let him down during a week crucial toward determining whether his path will lead toward the playoffs or a lost $500 buy-in. Smothers said he waited until Sunday morning to set his lineup because he wanted to be current on the latest injuries, but the outage meant his lineup became locked in with Patriots running back Stevan Ridley, receiver Brandon Lloyd and Buffalo quarterback Ryan Fitzpatrick all on the bench with lesser options in his lineup â¿¿ including one player on a bye.