"We need to win the next game at the Rose Bowl on Wednesday, simple as that. We wanted to peak for the Ashes because we'd been building up to that series for a long time.
"Now this could be a period when we start relaxing. But when you play against Australia, you can't give them a sniff," The Sun quoted Collingwood, as saying.
"Whether you are mentally tired or not, you have to go out and put in the performances. The schedules are the way they are and we have to get on with them," he added.
He admitted: "I go through periods when I'm feeling tired, mentally more than anything, but you get used to the treadmill of international cricket and I'm not going to make that an excuse.
The schedule is relentless but we can't complain - we're well-paid international cricketers."
England failed to chase 261 and 250 at The Oval and Lord's in the space of three days - and Colly accepted that was not good enough.
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