Joe Hart has admitted that he will be haunted by Frank Lampard's successful penalty that put an end to Manchester City's unbeaten start to the season.
Lampard sealed a 2-1 victory for Chelsea on Monday with a late penalty, and Hart is convinced that he should have saved the spot kick.
"As soon as the penalty was given I was talking to him. I realised the enormous pressure he was under, he'd just come on as sub and this was a massive moment, not just for him, but in the match," the 24-year-old told The Sun.
"Right away I was telling him 'I know exactly what you're going to do Frank. I know exactly where you're going to put it'. He didn't react at all but I know he could hear me and he admitted as much afterwards.
"But credit to Frank because he didn't say anything back, he just kept his head down. And so it all turned into this crazy mind game between the two of us, both trying to second-guess the other."
Lampard, who came on as a substitute, calmly slotted the penalty home to cut City's lead at the top of the Premier League table to two points.
"I was convinced I could save it but as I dived he blasted it straight down the middle," Hart added. "Now I can't get it out of my head. It just won't leave me. I can't stop thinking about it. I know I have to move on but this is really bugging me.
"It is so annoying. I should have known what he was going to do.
"It was so important for us and, knowing Frank like I do, I think I should have known where he was going. We do penalties together every day when we are with England, so I should have known."
Manchester City lead the Premier League with 38 points from 15 games.