Josh McCammon opened the scoring for the visitors on the stroke of half-time.
And Sports wrapped up the points when Dan Jarvis scored with the aid of a deflection off McCammon to completely wrong foot Hawkins.
It left Holleran to reflected on a poor result and a lacklustre display from his players.
"It was disappointing, as all defeats are, but they (Peterborough Sports) have come into the league and they look like an established National League North side,” he said.
“They play with confidence, they’ve got a lot of good players. We knew exactly what sort of game it would be and it was exactly what we thought it would be.
“The goal in the 44th minute from our point of view was poor. There was one mistake too many, we’ve dived in all over the place on the edge of the box, and in a cagey game where there was not a lot in it you’ve just got to come in and hope for a period in the second half.
"There’s ways to play at different times in the game, and that was not the way to play in the 45th minute, the way we did.
“The bottom line is, from an attacking point of view we’ve not been good enough.
"We haven’t got our shots off well enough, we haven’t been good enough in the final third; the ball hasn’t stuck enough; and when we have put three or four superb balls in the box we aren’t anticipating, reacting.
“It was a disappointing, frustrating day. Being bluntly honest there are too many players today, that have been 5 or 6 out of ten, and our knowhow and game management would probably be less than that.
"It is disappointing, because you’re coming to a stage of the season now, coming into December, where there’s going to be a lot of games like this. I think we looked a bit of a soft touch today; fragile.
"We got involved in things we didn’t need to get involved in, whereas they’ve just come and done a job. It was a good away performance from them and a disappointing home one from us.”
Meanwhile, Holleran has moved to sign cover for injuries to Ben Usher-Shipway and Joe Clarke by agreeing a 1 month loan deal with Northampton for midfielder Liam Cross.