Strauss has captained England in 54 one-day internationals, winning 24
Andrew Strauss still feels England can do well in the World Cup despite their latest loss to Australia that leaves them 5-1 down in the one-day series.
England failed to defend a total of 333 on Wednesday and skipper Strauss said: "We let them get too fast a start.
"We have one more game to show more of what we can do. We have a lot of talent and we can do a lot in the World Cup."
The series ends in Perth on Sunday, with England's opening World Cup game against Netherlands on 22 February.
One positive note for England in the two-wicket defeat was the performance of Jonathan Trott, who made 137.
Strauss said: "That is an outstanding score on any ground.
"Trott played outstandingly well but it was a good wicket and we weren't helped by Paul Collingwood not being able to bowl.
"We're very, very disappointed we weren't able to restrict them to less than 333 because that should be enough but they took the bull by the horns and were worthy winners."
Reflecting on the pattern of the series against Australia, Strauss said: "The first few games were tight but the Australians came through them and built some momentum and some of our batsmen got out of form.
"We're very disappointed but I am still very confident we are a very capable one-day side.
"We have shown plenty in the series but not all in one go."
Asked about the make-up of the England side, the skipper added: "We thought this was the best balance to win this game of cricket.
"I think in the World Cup we'll have to think about what the best balance is.
"This series hasn't helped our preparations really because we've had lots of injuries and haven't been able to play our best side. That was the same for Australia as well."
After his third one-day international century Trott commented: "It was nice to get a hundred but it is more memorable when you win."
Australia skipper Michael Clarke was delighted to silence his critics with his second successive half century and said: "I thought 333 would take some chasing."
Mitchell Johnson was an unlikely batting hero for the Australians, the enigmatic left-arm seamer, promoted to number four, hit two sixes and a four in 57 from 59 balls, only his second ODI fifty.
"We had to take a few risks and I had a bit of a punt on Mitch," Clarke said. "On the slow, low pitches at the World Cup he is a going to be a big player for us in the powerplays.
"I thought England batted really well and to go and chase those runs I'm stoked."