Christian Benteke scored either side of half-time and Andreas Weimann netted his third Premier League goal of the season as Paul Lambert’s side caused an upset on Merseyside.
A wave of optimism had swept across Anfield since recording successive league victories with a victory at Upton Park last weekend – but Rodgers warned the club’s fans there is still a lot of work to do.
“That was probably as disappointing as we’ve been here but I couldn’t put my finger on it,” said Rodgers.
“It is a strange thing football. We were talked up all week about us being top-four material but we know within the group we still have a long way to go.
“There is going to be steady progress and there are going to be steps forward, like in the last few weeks, and a step backward like yesterday.
“We looked at the first six months to assess: we know we need some support and hopefully we can get that in. We understand the process as well but the most important thing is to learn from it [the defeat].
“The thing we’ve learned from yesterday is that you can’t ever be complacent. You have to be at full tilt every week. If we do that we have a great chance of getting the points but if we don’t you can get punished.
“The challenge for us now is to have a good week’s training and come back next Saturday and hopefully get three points and get on the upward curve again.”