The NFL Network declined to comment when asked by SI.com and no formal announcement on Mayock is expected for several weeks.
Play-by-play announcer Bob Papa could be next on the hot seat.
Gus Johnson, who calls NFL games for CBS, is on the radar of executives at the NFL Network.
- Is There a Media Crusade Against the NFL?
- James Brown: 'I Challenge the NFL Community and All Men' to Confront Domestic Violence
- With Ray Rice News, James Brown and Scott Pelley Kick-Off Thursday Night Football
- Tim Tebow Joins 'Good Morning America' as Contributor