The two games that he's worried about is a Monday Night Football game on 9/26 with the Atlanta Falcons at the New Orleans Saints that would be on during the first debate. The second game he's worried about is the New York Giants at the Green Bay Packers on 10/9 during the second debate.
The NFL schedule was announced in April, and debate schedule was decided over a year ago. It could've been a Browns-Jaguars game and Trump would still cry about it. Let's face it folks, Trump is scared of conventional one-on-one debates.