The margin of the scoreline probably flattered Airdrie, but by no means did East Fife deserve anything from this game.
Darren Young's side looked to have recovered from last weekend's Scottish Cup defeat to BSC Glasgow when they put in a gritty performance in midweek against Clyde.
But there was nothing gritty about this showing at the Penny Cars Stadium, the Methil men second best across the park.
Airdrie were thumped 4-1 at Bayview earlier in the season and took out their revenge on the Fifers on their home patch.
The damage was done by the half-time interval, Airdrie sweeping into a three goal lead.
They netted another after the break to rub salt in the wounds.
East Fife were the architects of their own downfall with a couple of the goals but could feel aggrieved to have conceded others.
For Calum Gallagher's opener, the Methil men felt Chris Higgins was fouled by Sean Crighton on the build up.
If there was any doubt about the decision to award that goal against East Fife, Airdrie's second wasn't up for debate.
Callum Smith broke into the East Fife box where he raced past Stewart Murdoch.
The Fife defender looked to have pulled out of his challenge but the Diamonds forward took a tumble anyway.
Ref Gavin Ross pointed to the spot and Dale Carrick punished the Fifers with a terrific penalty tucked into Brett Long's corner.
East Fife were rattled and thing would get even worse before the interval when Carrick smacked home a terrific strike from the edge of the box.
It was pretty much game over by this point but boss Darren Young tried to salvage something, introducing Anton Dowds and Steven Boyd at the break.
Boyd added a bit of spark in the final third but all too often East Fife were guilty of wasting possession.
The game was just starting to peter out when the Diamonds put a bit of polish on the scoreline, Roy finishing off Smith's delivery.
Boss Young said : “The difference between that game and the one at home (East Fife won 4-1) was night and day and that’s disappointing.
“I’d love to say that a team has ripped us apart but that wasn’t the case, we cause our own problems and our own downfall.
“But their first goal is a foul and the referee has missed it and their second is never a penalty and the referee has missed that as well."