Andrew Flintoff said the strain of constantly coming back from injury had led to his decision Wednesday to announce his retirement from Test cricket in order to preserve his 'sanity'. The England all-rounder will quit the five-day game at the end of the ongoing Ashes series against Australia but the 31-year-old, who has so far played 75 Tests for his country, will continue to make himself available for selection for one-day and Twenty20 internationals. Flintoff was the star of England's 2005 Test series win over Australia as the team regained the Ashes for the first time in 18 years. But injuries have blighted his career and he now has to overcome a knee problem, sustained in last week's drawn first Test against Australia, if he is to play in the second match of the current Ashes series starting at Lord's here on Thursday. Asked why he was announcing his decision to quit Test during a series, rather than before of after the Ashes, Flintoff told reporters: 'It's something that has been in my mind for a while. 'Obviously the knee flaring up and getting the injections on Monday, it was a time I felt comfortable in doing it. 'There's been a lot of speculation about my future and I just wanted to get it out there, so we can get on with playing. 'Most of the lads have known what I've been thinking for the past few weeks anyway. 'My body is telling me things - I've actually started to listen now. I can't keep playing games here and there, waiting to be fit, for my own sanity, for my family who have had to live with me through two years of rehab in the past four.' And for all his influence, England have been more successful without Flintoff in recent times than with him. In the 25 Tests he has missed since 2005, England have won 12, drawn 10 and lost only three. By contrast, in the 23 matches Flintoff has played in that period, England have won three, drawn seven and lost 13. Flintoff, who had to have an operation of his right knee after injury in April cut short his stint in the lucrative Twenty20 Indian Premier League (IPL). 'After this series, I'll concentrate on one-dayers.' He said he hoped his decision could help him stay fit for the next two 50-over World Cups in 2011 and 2015. 'We've got a World Cup in 2011 and I'd like to play another after that as well. I think there is a lot of cricket left in me and I want to be the best in the world at that form of the game.' Flintoff said the fact England were involved in an Ashes series rather than it was, potentially, his final four Tests, was all the incentive he needed. 'You are playing an Ashes series, you are trying your best anyway. I can't try any more than what I do. 'It would be nice to finish on a high, having been involved in an Ashes-winning side before. It would be the perfect end to my (Test) career,' added Flintoff, captain of the England team thrashed 5-0 in Australia in 2006/07. He added he was hopeful of playing at Lord's, saying: 'I bowled today, provided there are no ill effects from that overnight I'm determined to play.' Flintoff said he felt glad to have made his decision public. 'There is relief but that is by no means going to effect how I go about preparing for this Test or any others. I still feel over the next four Tests I can play a major role in the side's success.' Flintoff, who has had four operations on his left ankle, said he'd been at his best in the early years of Michael Vaughan's stint as England captain which began in 2003 'I think the two or three years after that were the best cricket I've played. But I've missed two out of four years. 'My career has been curtailed a bit by injury. But as a bowler, apart from the body, I think I am getting better and I can nearly bat again. So my best years might be in front of me, but not in this form of the game. 'In Test cricket, you look at the schedule ahead of us and I wouldn't get through that,' Flintoff said. And he insisted he had no interest in pursuing a career as cricket broadcaster. 'I've got no ambitions of rattling on down a microphone, I want to perform with bat and ball. 'I can't grumble too much. If someone said you'll play 75 Tests, I would have snapped their hand off. 'I started at 20 and I was rubbish. I would probably have liked my career to have kicked on after the Ashes but rehab makes it difficult. But I don't have any regrets, I'm happy.' Flintoff has a year left on his contracts with Lancashire and IPL side Chennai Super Kings. 'I'll see what they want from me and what I want to do as well,' he said. 