Play was abandoned due to the rain during the third Test in Manchester with the Baggy Greens seemingly in control, leaving the match as a draw and England with a 2-0 lead in the series with two Tests left to play.
However, Warne feels that Australia have shown enough in the three matches to suggest that they can win the urn back on home soil but admits that they will feel bitterly disappointed.
"I think they would have learnt a lot," Warne told Sky Sports News. "I think it's taken them a couple of Tests to work out what their best team is but they'll be disappointed; they've declared twice in this game and if the rain hadn't had come I think they would have won today.
"I thought Australia were outstanding today. They had to take some early wickets to give themselves a chance and they did, and they had lots of time to take the remaining wickets once they'd got into that middle order. So it's a real shame for them because they will have felt that they had a big, genuine chance of winning the match from that position and make it 2-1 in the series. They'll now have to cope with the disappointment that they can't win the Ashes.
"They have to get themselves off the floor because they can take a lot out of this Test match and say 'if we play like that again' we can beat England. Their number one goal now has to be to level the series - if they can do that then it is set up to try and win back the Ashes in Australia."
The Ashes series in Australia starts on November 21.