Villa have slipped into the Premier League's bottom three following a run of eight games without a win, while a number of their rivals have found form in recent weeks.
Lambert has no complaints about the work ethic of his players and there have been some encouraging displays, such as the 3-3 draw against Everton and even the second half of the 2-1 loss to Newcastle.
However, the manager recognises that only points matter at this stage of the season and made his message clear at a squad meeting this week.
"We had a chat the other day - they know what they have to do," said Lambert in The Sun.
"We're in a fight and it's horrible but winning covers a multitude of sins. If you play poor and win, you'd take that.
"I know we're in the entertainment business but sometimes that doesn't get you anywhere.
"The effort of the players is there in abundance. We all believe they can do it."
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