London: Australia coach Justin Langer admits the form of Glenn Maxwell is a concern ahead of Thursday morning's ODI against England at The Oval.

Maxwell failed again with the bat against Middlesex on Saturday in Australia's comfortable 101-run warm-up win at Lord's, scoring just three.

It followed his dismissal for just one run against Sussex and a lean IPL campaign for the Delhi Daredevils where he averaged 14.08 in 12 visits to the crease.

The talented Victorian is the only member of Australia's established batsmen not to get any extended time in the middle since arriving in the UK but Langer believes Maxwell is too good to be out of the runs for long.

"He is (a worry) but that said I have been super impressed with Glenn Maxwell, his preparation has been literally outstanding," Langer said. "I would be very surprised if he doesn't get a very big score very soon.