The Ashes: We have exposed some cracks in England's top-order, says Darren Lehmann

Australia coach Darren Lehmann believes his side have exposed some "cracks" in England's top-order batting which they will look to widen before the end of this Ashes series.

The tourists' hopes of regaining the urn were washed away by a rain-affected third Test draw at Old Trafford on Monday, helping England take an unassailable 2-0 lead with two Tests to play. (Also read: David Warner may be back as opener for fourth Test)

But a much improved display at Old Trafford saw Australia make a first innings score of 527 for seven declared, which included captain Michael Clarke's superb 187, after they'd been bowled out for just 128 first time around in a crushing 347-run second Test defeat at Lord's.

In the hosts nailbiting 14-run first Test win at Trent Bridge, England's Ian Bell made a hundred and he did so again at Lord's where young opener Joe Root weighed in with 180. (Clarke's 24th ton rockets him to world No.2)

However, it was a different story at Old Trafford where Kevin Pietersen's 113 was all about helping England avoid the follow-on.

"The first two Tests, Root got a big hundred and Bell's made a couple -- but we've shown a couple of cracks in their batting, which is exciting for us as a bowling unit," said Lehmann. (Allan Border says Australia looking dangerous again)

Asked if by that he meant England captain Alastair Cook, Jonathan Trott and Jonny Bairstow -- all still searching for a major score this series -- the former Australia batsman added: "It's not just those three.

"We have some great ideas about the other eight batters -- which is good."

Lehmann was understandably delighted by the way Australia, for whom this draw stopped a run of six straight Test defeats, responded to their humiliating loss at Lord's.

"After Lord's, it was a real test of character," he said ahead of Friday's fourth Test in Durham.

"They passed with flying colours. We dominated the game. We have to repeat that at Durham. Making big runs helps.

And the Old Trafford first innings also saw Australia deny James Anderson a wicket on his Lancashire home ground as England's spearhead toiled for 33 overs without result.

"The more overs he bowls the less wickets he will get. We played him better than we did at Nottingham (where Anderson took 10 wickets in England's 14-run first Test win)," Lehmann said.

"He's a great bowler. We have had our plans and maybe we haven't executed them well enough."

Australia pacemen Ryan Harris and Peter Siddle both posed England problems in Manchester and Lehmann added: "I think we've bowled really well.

"England made big runs in the second innings at Lord's, but that was because our batting was disappointing.

"We didn't make enough runs. So what we have to do is make sure their bowlers bowl a lot of overs."

Meanwhile Lehmann was cautiously optimistic the injury-prone Harris could cope with the strain of back-to-back Tests.

"I think he's a reasonable chance. If he'd bowled (a lot in the second innings in Manchester) I wouldn't think he would be a chance at all.

"For us the most important thing is actually backing that performance up again. Our last five days have been outstanding, putting England under pressure, and we would have won the Test match.

"So we're quite comfortable with that."

Lehmann was also heartened by the form of David Warner, who made 41 after being pushed up to open in the second Test.

Warner missed the first two Tests after punching Root in a Birmingham bar during the Champions Trophy two months ago.

"He has gone through a difficult time," said Lehmann. "He played really well in the second innings.

"He knew he was going to cop a bit from English crowds, and that's just part and parcel of what he did.

"We would love him to make some big runs, and that's what he is in the top six to do."