Fleet's manager played in the Kent Cup tie against Bromley.
His performance couldn't prevent the team exiting the competition as much changed United bowed out 1-0 to Neil Smith's Ravens.
Injury issues forced his hand - and the 33 year old, who hasn't played for nearly two years, decided the time was right for him to return to action.
"It was good for myself to play with people,” manager McMahon told BBC Radio Kent.
"To see what they’re seeing sometimes that you can’t see from the sideline while you’re on the pitch and you can coach on the pitch which is nice.
"We haven’t got many bodies to spare at the minute so it was good for me to get a sweat on and have a little game of football!”
The manager may have a new defender in place for the Bank Holiday double header.
“Hopefully we might have one in, we’ll see,” he said to the station. “With the transfer window in the Football League, people aren’t looking to let players out until that closes.
"At the minute it’s pretty much a closed shop. We’re hopeful but we’ll wait and see."
Ebbsfleet are at home to Gateshead on Saturday before a big Kent derby with Dover Athletic on Monday.