The Bulldogs trailed by 44 points after 13 minutes of the final quarter before kicking the last seven goals of the game, eventually losing by three points.
Liberatore, who finished with a career-high 36 possessions (17 contested) and 12 clearances, said the players were disappointed they took so long to play aggressive football and attack.
"In the first three quarters we were playing selfish footy and we didn't really care about how we got dragged around by Melbourne and we went into our shells," he said.
"It's just disappointing because we know we can do it. It's embarrassing [and] we know it wasn't good enough for three quarters.
"We'll stick together and rebound and do our best next week."
Coach Brendan McCartney said the Bulldogs showed they could play good football when they did the basics well, backed themselves and pressured the opposition, as they did in the final term.
However, for three quarters McCartney said his players showed that when they don't all work together "you can look very vulnerable".
"Parts of our game and parts of what we were doing were very disappointing," he said.
"The basics of the game let us down heavily tonight.
"We just didn't put anywhere near enough defensive pressure on Melbourne in the front half of the ground in the first three quarters.
"We're still at the stage where if we have an area of the ground that gets beaten comprehensively, we get into strife."
The Bulldogs' late run was sparked by midfielder Ryan Griffen and ruckman Will Minson, who had 20 of his 51 hit-outs in the fourth quarter.
Brownlow medallist Adam Cooney also lifted, kicking back-to-back goals to cut the margin to 14 points.
"It's a funny thing, the human psyche. Sometimes you kick a couple and you think, 'well, let's have a crack at it'," McCartney said.
"Our good players certainly got up and running.
"The disappointing thing is we took so long to actually play like that."
McCartney said the Bulldogs' run started partly as a result of substituting out disappointing tall forward Liam Jones in the third quarter.
"There were parts of his game that weren't what we wanted," the coach said.
"We had a young creative player sitting there ready to go (Lachie Hunter) so Liam needed to play better tonight to stay on the ground.
"We got rolling a little bit when we made that change."
Nathan Schmook is a reporter for AFL Media. Follow him on Twitter: @AFL_Nathan
