STEPHEN Harmison warned last night that Darren Gough, currently fighting a long-standing knee injury, must be at the peak of his powers this winter - or England will face further Ashes misery.

Harmison made his gloomy forecast as he prepared to fly out to Australia today with the rest of the England squad ahead of the toughest challenge in cricket.

The Durham paceman knows Gough's likely absence from some of the five-Test series - the England talisman has already admitted he is likely to miss the first two matches next month - will improve his chances of figuring against Australia.

But as he counted down the hours before he heads Down Under, Harmison insisted his country's Ashes hopes would be dealt a fatal blow should Gough's participation in the series be restricted.

Harmison, 23, said: "We need Darren Gough fit. We can't do without players of his quality.

"The best side doesn't always win a series. If we get the rub of the green this winter and get our core of four or five key players fit, we've got a chance.

"But Darren is the best English bowler without a shadow of a doubt. We're a lot stronger with Darren in the side.

"I would love to get in the side and keep him out because that would mean I'd done quite well.

"But the fact is I'm not in the squad to take Darren Gough's place and neither is Simon Jones.

"At The Oval last month, there was talk that the final place in the side was between myself and Andy Caddick.

"But in my mind, there was never a choice. Andy and Darren have been England's best bowlers over the last five years, and we need them fit and firing on all cylinders against Australia."

Harmison is the first Durham player to make a full England tour and is keen to kick-start his Test career after fortune smiled upon him this summer.

After a promising debut against India at Trent Bridge, the Ashington Express was omitted from the England side for the Tests at Headingley and The Oval.

But the Indians tore apart the home attack in both matches, and Alex Tudor paid for two disappointing performances with his place in the Ashes party.

That spot went to Harmison, who said: "Not playing in the final two Tests did me more good than harm because our lads didn't bowl very well.

"They gave people enough rope to hang themselves with, and they've done that.

"Alex Tudor played in the two games and it didn't go well for him, and subsequently he lost his Test place."