Clarke will step down as Australia skipper after the fifth Ashes test, which starts at 8pm AEST on Thursday.
The 34-year-old has categorically ruled out a draw in the dead rubber.
That's not a comment on Australia's batting, which has been woeful throughout the Ashes, but an exceptionally green pitch at The Oval.
"I haven't gone and looked at the pitch yet but the stumps are in the wicket so it's obviously not going to change too much," Clarke said.
"It still looks pretty green from the boundary, so I'd imagine it will look even greener up close.
"I think it's going to be another really tough test match for the batters.
"We just have to find a way to fight our backsides off, whether it goes two days or three days I'd just like us to be on the right side."
Clarke indicated earlier this week he expects the winner of the toss will bowl first.
Australia suffered a collapse of 5-60 on day one of the third test, while Stuart Broad snared 8-15 to skittle them for just 60 in the fourth test.
The tourists were never going to fight back from that position and proceeded to hand the urn over with an embarrassing loss of an innings and 78 runs in Nottingham.
Clarke had mixed feelings about leaving on such a low note.
"There are no fairytales are there? I'm extremely grateful I've been able to play this long for Australia," he said.
"It's the right time for a number of reasons. I'm more than happy to leave.
"I would obviously have liked us to play better in this series, and certainly me personally.
"But that's the way it goes."
