Vikram Solanki's daily Ashes column

What a day on which one of England's toughest cricketers should signal his impending retirement.

Paul Collingwood has been a terrific servant to English cricket and a 68-Test career which has included winning the Ashes three times can point to many highlights.

But even in his wildest dreams he could not have expected to announce his retirement with his country's boot pressed so firmly against the throat of Australian cricket and in their own backyard.

A word on Collingwood. As ever he was bluntly honest about his situation as he now steps away from the five-day game to focus on the limited overs version which provided his gateway into the Test team and in which he is still one of our leading players.

He acknowledged his poor scores during this series and the fact that, behind him, there were younger cricketers straining at the leash to get into a team which is advancing all the time. His was no wish to delay their progress.

But let us not under-estimate his contribution to this group and their current domination of the Aussies.

One wonders if things may have been any different for Australia in 2009 if they had been able to press home their advantage and win the opening Test in Cardiff -it was a gritty Collingwood innings which did much to defy them.

I think it's fair to say that, as a cricketer, those were the kind of situations in which 'Colly' thrived. Give him a backs-to-the-wall scrap and his competitive heckles were raised to new levels.

Maybe one of the reasons we haven't seen him score any big runs in this series is because those situations have been few and far between - England have been so on top and so ahead of the game on so many occasions, the scrapper in Collingwood has not been required.

What a shame, though, that he couldn't manage a hundred because when Matt Prior played so beautifully this morning to reach his three figures, it occurred to me that six out of England's top seven had registered centuries in this series, 'Colly' missed out on making it a full complement.

In contrast none of the Australian top four have achieved that landmark and you simply cannot hope to compete in a series with such an imbalance between rival units.

So we had another brilliant day for England, from their building of a lead which is off the charts from what even they would have hoped for when Collingwood was dismissed at 226-5.

And then the bowlers got to work again helped, of course, by still further signs of the current distress of the host nation.

I don't necessarily think it was a game-changing moment because with such a lead, England were always going to win this Test in my view, but the run-out calamity between Shane Watson and Phil Hughes which started the wickets tumbling was typical of what can happen to a side under such overwhelming scoreboard pressure.

The seamers chipped in with two wickets apiece thereafter, Jimmy Anderson continuing to bowl quite beautifully, and Chris Tremlett striking dramatically to continue his excellent advance in this series.

The Aussies have attempted to neutralise Graeme Swann by leaving grass on this pitch; he is a genuine spinner of the ball and it simply hasn't turned.

But do not under-estimate what a precious job Swann brings to the team in such circumstances.

He bowls with such control and yet still enough of a sense of attack that he continues to apply pressure to the opposition. When you are operating with a four-man attack, it is heaven for a captain to be able to have a bowler such as Swann.

I expected England to win this series as I outlined at the beginning. I felt it would be close, however, with one Test separating the teams. Never did I imagine we would see England winning by such crushing margins.

For all of us who remember the domination Australia enjoyed for so many years up to 2005, it is a sweet moment.

England have a depth and a strength about them at this moment which is reminiscent of their old rivals 10, 15 years ago.

Collingwood is stepping aside to let it through and continue the exciting advance of being made under Andrew Strauss and Andy Flower.