Tranmere slipped out of the top six over Easter and were dealt another blow as npower Championship-bound Doncaster completed a double over them, after skipper Rob Jones grabbed the all-important goal in the 63rd minute.
"It's disappointing because it looks like a goalless draw all the game. I just couldn't see anybody scoring unless it was a 35-yarder or a piece of magic," Moore said.
"But they got a free-kick and one centre-half heads it down to the other and bang - it's in the back of the net.
"They are a big, strong side and we had talked before the game about cutting down the corners and free-kicks we allowed them.
"It was the second ball that did us. When the ball was headed down our reaction was poor and that's been the case too often.
"It was a tight game and I can't fault our commitment, effort and desire, but one mistake by a defender has cost everybody."
Doncaster always had the edge in a hard fought clash and just about deserved to grind down their opponents.
The victory put Doncaster seven points clear of third place, but manager Brian Flynn said: "We haven't set a points target and I've no idea how many more we need to win.
"The games are a grind at this stage of the season, but we just need to stay consistent and keep our form going and we'll get there."
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