Liverpool midfielder Javier Mascherano admits he has struggled to find his best form this season.
The Argentina captain says he knows he can do much better and believes a return to his 2008 form is crucial in keeping the club's title hopes on track.
Mascherano says his confidence has taken a knock after his performances have failed to live up to his own self-imposed high standards and he said last summer's Olympic Games have left him lacking his usual energy and drive.
He said: "I know I have not played like my old self this season. I can do much better.
"I think maybe it is because it has been a long season already for me and that maybe my confidence is not as full as it was last season.
"The Olympics have definitely had an effect on my form and my ability this season. I should be playing better for Liverpool than I am at the moment."
The Reds are on a 15-match unbeaten run, but seven draws in their last 11 Premier League outings have been severely damaging to their title hopes.
It has allowed Manchester United to regain top spot - with Chelsea, Sunday's visitors to Anfield, moving into second place on goal difference.
There could hardly be a better time therefore for him to bounce back to his best - and he is determined to do so.
"I want to promise people one thing," Mashcerano said. "I am trying every day in training and in games to get back to my best performances.
"This is not my best season, I know that last season I was a lot better. I am not a liar and I am not stupid.
"I know I can do it - that is why I don't mind admitting it. If you cannot see the problem to analyse it, you are not going to be able to resolve it."
Mascherano's dip in form, plus the failure of Robbie Keane to make a genuine impact, are two of the roots of Rafael Benitez's problems with tactics and team selection.
Benitez said: "Javier is right, because he needed time after the Olympic Games. But now he is coming back to his best.
"He just needs to keep working like he is doing every single day. You can see his commitment in training."