In the last three matches the Reds have surprisingly lost at home to Aston Villa, hammered Fulham 4-0 and then capitulated at Stoke having been a goal up.
Instead of being within touching distance of the top four, which was the main aim this season, Liverpool are 10th and looking an increasingly distant eight points back.
The lack of bite was a concern at the Britannia Stadium, where the Merseysiders invariably have a bad time having failed to win there since the Potters' promotion to the Premier League, and Rodgers admits they have to toughen up physically and mentally.
"If you are going to affect the top of the league, which is what we want to do in years to come, you have to have more steel than that," said the Reds boss.
"But if you concede goals like that it is going to be difficult to win games anywhere.
"Every game is learning. We learned after the Villa performance and responded well against Fulham and I am sure we will get a reaction on Sunday.
"But we want to be more consistent than that. We can't be reacting all the time.
"You have to create your own mentality that keeps you consistently getting results and that is something we are working on to achieve.
"As a group, we work on all aspects of the game, tactically, physically and mentally.
"You cannot play at a top club without all those aspects. It comes from within and especially when you go away from home.
"But we will stay very much together as a group. We are all disappointed with the Stoke defeat but we'll regroup for the weekend."
Liverpool will face a different kind of battle on Sunday when they head to struggling QPR, who are scrapping for their top-flight survival.
"It will be a difficult game against QPR, who are fighting for their lives, but it is never an easy ground to go to," added Rodgers.
"They will want to react after losing (last weekend) but my only concentration is on ourselves."
Defender Jose Enrique (opposite page) admitted the players should have done better at the Britannia Stadium, especially after being gifted a goal in the opening minute with their first penalty for 32 games.
"We need more experience and need to show more character in these type of games," he said.
"You can see we have quality players and we have a good squad but we need to fight for every point we play for if we want to be in the top four.
"We have to get a winning mentality going and we have to show what we are all about.
"We need to bounce back from this defeat and we need to go to QPR and win.
"Every game in this league is difficult but you have to give 100 per cent every time you play for this club and show character."