Australia captain Pat Cummins was left to rue "key moments we didn't get right" after his dream of leading the side to an Ashes series win in England was scuppered on Monday.

At 264-3, chasing a mammoth target of 384, Australia had a chance to pull off an improbable victory on the last day of the fifth and final Test at The Oval.

A draw would have been enough to have sealed the series.

But instead they suffered a dramatic collapse, losing their last seven wickets for 70 runs, as England won by 49 runs to end the series all square at 2-2 -- the same result as the 2019 Ashes.

"There's a couple of key partnerships batting-wise that it felt like if we just put on another 50 runs or so, it could have turned the tide in our favour," said Cummins, talking about the series as a whole.

Monday's defeat left Australia still searching for a first Ashes series win in England since 2001, even though the 2-2 draw meant they retained the urn.

The tourists were faced with a gruelling schedule of six Tests in eight weeks, starting with last month's rout of India in the World Test Championship final at The Oval.

"We just missed what we were hoping to come over here to achieve," said Cummins.

"But winning the World Test Championship and retaining the Ashes, it's a pretty successful tour."

The 30-year-old fast bowler also regretted off-spinner Nathan Lyon's tour-ending calf injury in the second Test at Lord's.

"It's pretty clear just how important Nath is in all conditions," said Cummins. "We probably felt that at times at Manchester (where England had the better of a rain-marred drawn fourth Test), not having a spinner out there."

Cummins said he was well aware that for all Australia's recent triumphs elsewhere, his side would be judged on the Ashes.

"Whether we like it or not, Ashes tend to define eras or legacies," he said.

"If that is the case on this one, it's something we can be really proud of. The last two series over here we retained the Ashes.

"That doesn't happen very often... the group has had some amazing achievements over the past few years, so if it is a legacy, that is one I am happy to have."