According to Jay Glazer of FOXSports.com, the National Football League is investigating the San Diego Chargers for possibly using an illegal "Stick 'em"-like substance during their 35-24 loss to the Denver Broncos last Monday night.

"NFL Security has already begun investigation as SD equipment man was hiding illegal sticky substance and giving to players. Line judge saw it and had it confiscated and sent to Broncos and league", Glazer posted on Twitter.

The Chargers released a statement later on Sunday.

"We are aware of the inquiry and we are cooperating fully with the League," the Chargers announced on their official website.

The equipment manager had the substance hidden in hand towels and the line judge (Jeff Bergman) noticed it during a timeout and made the equipment manager in question empty his pockets. The NFL takes issues of competitive advantages seriously and Glazer adds that sanctions by the NFL could range from a substantial fine to the possible forfeiture of draft picks, the latter of which may depend on how many individuals were involved in using or distributing the illegal substance.