Darren Young said his side never gave themselves a chance after losing another early goal at Ayr.
The Methil men went into the game having won four and lost three of their opening seven league games.
The stuttering nature to East Fife’s beginning to the campaign has been a source of frustration.
And on Saturday they fell to defeat at Somerset Park, as one of the division’s title favourites won convincingly.
Boss Young said: “It’s really frustrating because the side has set a standard over the past couple of weeks with some good victories.
“Ayr are a full-time team but against anyone in this league we’re looking to compete.
“It’s really disappointing that we lacked that.
“We had two wins before the Raith game and went into that on a high and going in to attack them.
“We maybe left ourselves open so went with a defensive midfielder instead against Ayr to make it difficult for them.
“But we lost a goal in four minutes in the Raith game and lost another early on in this.
“We shoot ourselves in the foot before the game plan could even come into action.
“It’s really frustrating and really disappointing.”
The home side took the lead in seven minutes when Lawrence Shankland bundled the ball past Mark Hurst.
The hosts started the second half in the same manner as the first and again scored early.
Shankland was creator this time, his cut back into the penalty box rattled home by Andy Geggan five minutes after the restart.
Any hope the Fifers had of somehow getting back into the game took a severe dent when captain Jonathan Page saw a straight red for a studs up challenge on Declan McDaid.
The game was put firmly out of East Fife’s reach when Chris Higgins was on hand from close range to add a third 17 minutes from time.