IT is fascinating to watch this England side disintegrate before our very eyes.

What had looked like one of the most settled Test line-ups in world cricket is suddenly being ripped apart, as if Mitchell Johnson had not just taken aim at England's batsmen but at a giant teamsheet as well, his 90mph rockets bursting gaping holes in the brittle paper.

In the past several years, there have only been two positions up for grabs for aspiring young Englishmen. The first was that of the No.6 batsman, vacated by the mostly undislodgable barnacle, Paul Collingwood - now coaching Scotland - as well as the third seamer to back up indisputable regulars James Anderson and Stuart Broad.

Now, suddenly, Jonathan Trott is gone, likely never to return; Graeme Swann has bowed out with an incomprehensible dig at who knows who; Matt Prior is clinging on to his place by the tips of his gloves; and even Anderson has struggled on flat wickets which offer little to his medium-paced, swingy technique.

While England have arrived at an unanticipated period of transition, it is also the perfect opportunity for Australia to stamp their inexperienced opposition into the dirt and bestow a few mental scars which might linger until 2015.

The latest casualty, Swann, one of those never short of self-confidence, left the stage as he lived on it, with one last straight-talking interview in which he appeared to criticise some members of his own team. It remains unclear who he was referring to, but the spinner has been known to criticise Kevin Pietersen in the past, and the South African-born batsman seems unlikely to ever join Swann down the village pub for a couple of post-retirement brandies. In his autobiography of two years ago, Swann wrote that Pietersen was 'never the right man to captain England'.

On Sunday, he said: "Some people playing the game at the minute have no idea how far up their own backsides they are. It will bite them in the a*** one day, and when it does, I hope they look back and are embarrassed about how they carry on."

It was an embarrassingly, petty way to bow out of the Test arena, one last attempt to steal the spotlight; the cricket equivalent to those eager, keyboard-wielding attention-seekers who clog up social media feeds with their inane rants against unidentified 'haters', desperate to be asked to elaborate. He pointed out yesterday: "I wasn't talking about the England dressing room or anyone in it."

Well, who then? The Australians? "Swanny probably knows who he is referring to," said Monty Panesar, with not the greatest insight. "But in terms of the dressing room and the team-mates, we're right behind him. We loved him to bits when he played."

Swann certainly loved the experience, eulogising about his part in England's recent success. "I hope my legacy is someone who always enjoyed it, who played with a smile on his face," he said. "Sometimes a snarl when the fielders misfielded. Since I got back in the England team, I've treated every day like a lottery win. It really annoys me when people take it for granted and get above their station, because they shouldn't," he added, with a final stab at someone.

Panesar will be the man to fill his shoes, in the short and probably medium-term as well. It might have been coming anyway; Swann's decision to trudge off, broken, into the sunset - coincidentally just as his bowling average was about to creep above 30 - might have pre-empted his being dropped.

England have been quick to call in back-up: Scott Borthwick will join the squad in time for Melbourne, and James Tredwell will arrive to form a spin-trio in time for Sydney in the new year, a ground which should suit the twirlers. Still, the ball is very much in Panesar's hands for now, although the spinner recognises that he will need to improve. At 31, he already has 166 Test wickets to his name but is under no illusion that he has much to do if he is to merit mention eventually in the same breath as Swann.

"He has set the standard for spin bowling around world cricket," Panesar said of the off-spinner who finished this series with just seven wickets at 80 runs each.

"When you lose your own hunger for bowling, or your own passion, you know your time is up. He's done wonderful things over the last few years. I'm replacing an icon player. He'll be remembered as one of the greats. He has done phenomenal stuff for the game.

"If I can reach half of what he's done, I'll be ecstatic. I definitely feel ready coming into this Test. I'm really excited. The Boxing Day Test in Australia is a huge occasion and excites all of us."

Panesar, who left the England squad temporarily at the weekend to bowl in a grade match in Sydney, is eager to play his part as England seek to prove they are capable of better than they have shown so far this winter. "Opportunities that come my way, I've got to grab them," he said. "I know my strengths as a bowler and try and to make the most of the opportunity and be ready for it. There are improvements I need to make in my game. I've made a decision to play grade cricket after the Ashes, because I want to improve."

Panesar takes issue with the observation in some quarters that England's tour, comprising three successive landslide defeats to date and beset by a variety of off-the-field setbacks too, has become a 'joke'.

"We're all disappointed with the way the results have been," he said. "Credit has to go to the Australians, how hard they've come at us and how ruthless they've been. We've got two Tests where we want to show some fight . . . to show a bit more resilience than we've probably shown in the last three Tests. I don't think it's become a joke at all. We're a determined dressing room, determined to make the most of these next two Tests."