Australia have not recovered from a 2-0 Ashes deficit since 1936-37 when arguably the world's finest ever batsman, Sir Donald Bradman, was the source of their inspiration.
In the 76 years that have passed since, Australia's batting stocks have hardly looked as bare as they do now - highlighted by the performances in the opening two Investec Tests.
Teenage spinner Ashton Agar is the tourists' leading run-scorer, while only Clarke and Shane Watson have passed 100 aggregate runs.
Even more alarming is that paceman James Pattinson, ruled out of the series with a back injury suffered during the 347-run mauling at Lord's, has the highest batting average at 36.
Australia could be reinforced by the return of controversial left-hander David Warner, after he hit 193 for Australia A during his exile to Africa last week, but Clarke is wary on pinning his faith on the return of one man.
Instead he believes his entire batting unit must step forward in Manchester if they are to kick-start a comeback he concedes is a laughable notion to most right now.
"I honestly believe we can win this series," Clarke said.
"I know there's a lot of people out there that will laugh at me saying that. But I wouldn't be here today if I thought this team wasn't good enough to have success.
"The reality is our backs are against the wall."
Asked if Warner, who returned to the squad this week after being sent to the second-string tour as punishment for punching Joe Root at a Birmingham bar following the Champions Trophy defeat to England last month, he added: "I don't think it's about one individual player.
"I think it's going to take the whole squad and definitely the whole 11 players who take the field for us to take the series.
"It's about performances and standing up and being accountable for our own performances. Hopefully the batters can lead the way.
"We've plenty of experience in that group of batters we have on this tour. We need to make sure we are scoring more runs than we have done so far.
"There are difficult times in your innings as a batsman.
"It is about respecting those periods and then when you get on top to play with that aggressive intent."
Warner is a player who would provide the type of on-field aggression Clarke and coach Darren Lehmann favour, while his near double-century against South Africa A in Pretoria marks him as one of the few players to have some form to call on.
Clarke reckons also that the apologetic opener has learned from the fall-out of the Root incident, meaning Australia could be ready to bring him back for a match in which anything but victory will end their bid to return the urn.
"He's got 190-odd runs under his belt which is obviously a positive considering our batters haven't made many runs so far on this tour," the 32-year-old said.
"I think Davey at the time made it pretty clear that he was extremely apologetic for what occurred. He knows what the expectations are as an Australian cricketer.
"I am very confident that he has learnt from what happened in the past, is trying to put that behind him and move forward, and I think he is doing a really good job at this stage."
Should Warner return, Australia must decide which batsman to drop with Steve Smith - who made a century in the tour game at Sussex last week - under a fitness cloud.
Smith sat out Tuesday's practice session with a bad back but trained on Wednesday.
The 24-year-old underwent a brief fitness test on the field before joining the main group in the indoor nets, where former leg-spinner Shane Warne even briefly bowled at them.
"He's a lot better than he has been over the last couple of days," Clarke said of Smith.
"I think they'll do everything they can to give Steve the best possible opportunity to be right for tomorrow [Thursday]."
Should Smith be passed fit, Phil Hughes appears the man most likely to make way after he managed two scores of one at Lord's.
The left-hander did manage 84 in the preceding tour game at Hove, during which time openers Watson and Chris Rogers stayed away from the squad to work on their games.
Watson is the only batsman yet to pass 50 as the England bowlers have homed in on his front pad, dismissing him lbw in three of his four innings to date.
"Shane has been working very hard on his game. There is no doubt about it," said Clarke, who acknowledged he too was in need of a significant score.
"Like all of us, he'd like a few more runs and he has been working hard in the nets to give himself the best chance."