Michael Clarke's Test match career could be over after the Ashes if he doesn't rediscover his best form, according to former fast bowler Jason Gillespie.
The Australia captain has struggled in his six innings and has a top score of 38, while the tourists trail England 2-1 in the series.
Gillespie wrote in The Guardian: "Only one person will know whether the Australia captain, Michael Clarke, truly has a future in Test cricket beyond this Ashes series, and that is the player himself.
"Scrutiny over his place in the side has intensified after the eight-wicket defeat at Edgbaston, where he was honest enough to admit that, as a batsman, he has yet to get off the plane.
"Quite simply, Clarke is the number four for Australia and he has to step up and do his job if England, sitting 2-1 up after three Tests, are to be prevented from regaining the urn. He knows 94 runs in six innings is not good enough and while people can talk about technique or physical issues that may be affecting his game, he must be judged on his output, which is run-making."
The fourth Test begins on Thursday.
