Alastair Cook has managed to do it all this year. He's been a captain living on borrowed time, an English hero, and a skipper apparently putting his own ego ahead of the best interests of the team, and he's somehow found time to fit all of that in during one summer.

After months filled with questions over his future, one thing is absolutely certain. The time has arrived for there to be changes in the England camp, but has Cook left it too late to ensure that his reputation is not tarnished by a summer of discontent?

It was never going to be an easy year for Cook and his players. Losing 5-0 in Australia is only going to raise concerns about the long-term future of both captain and team, but their response to a disastrous winter has left their supporters experiencing flashbacks to the dark days in the 1990s.

Struggling in the West Indies and a disappointing World Twenty20 campaign had piled the pressure on Cook ahead of the English summer, despite the 29-year-old not being involved in the latter of those concerning set of performances.

The cricketing gods simply weren't on England's side as they welcomed Sri Lanka early in the season, with the tourists following expected limited-overs success by shocking the hosts with victory in the Test series which followed.

Cook appeared to be lacking ideas out on the field, and the questions over his ability to captain an international team returned, with his critics agreeing on the view that he was not the right man to carry a new-look side into a new era.

The truth is, whether they wanted to admit it or not, the England fans wanted their team to recreate the intensity shown by Australia, who were on the front foot throughout the winter with their aggressive brand of cricket in the longest format.

However, supporters dreaming of Cook transforming into Michael Clarke overnight would be waiting a long time. He is a different person, and it's doubtful that he'll ever approach the game in the same way as his Australian rival, but was that his fault?

Cook, tipped by many as a future captain as soon as he made his Test debut in 2006, could have packed it in as soon as the criticism started to arrive at his front door, but this is the same skipper who guided England to a famous series triumph in India just 18 months earlier. Was it Cook's lack of a killer instinct, or are England simply not the same team they had been over the past few years?

It's been a torrid summer, and the concerning results have been joined by criticism of the ECB for their decision to sack Kevin Pietersen earlier in the year. Cook has been seen singled out for his part in that move, and he may never win some fans back over.

Few would ever doubt the suggestions that Pietersen divides opinion in the cricket world, but he is a match winner, and if there was something Cook has been searching for throughout this miserable saga, it's been a player capable of carrying some of the pressure on their shoulders.

Another defeat at Lord's, this time against India, saw even more questions asked, and there were certainly signs that Cook was changing his approach when it came to answering those who doubted him.

In fact, it's been refreshing to see an England captain take so much pride in his position, but even after his side responded to beat India 3-1 in the longest format, it was clear that his backers were diminishing by the day.

In the first week of September, England are at a crossroads yet again, and a lot could depend on what Cook does next. His eagerness to fight for his position as captain of both the Test and ODI teams is now coming across as stubbornness as he desperately clings on for a place in the team in the shorter format.

Cook can't escape the facts. His team simply don't have a chance of challenging at next year's World Cup playing the kind of cricket they've produced in the ODI series against India. There must be changes, and for the good of Cook's legacy, he must hand back the ODI captaincy.

Four half-centuries in the latter stages of the Test series certainly helped Cook out, but he's looked uncomfortable once again at the top of the order in ODI cricket. The ECB are always talking about "executing our skills", but maybe it's finally time to accept that Cook's skills will not lead him to become a great player with the coloured clothing on.

Is there any shame in walking away to concentrate on Test cricket? No, certainly not. However, the longer Cook takes up a place in the team, the more of his followers he will lose. The big challenge for Cook should be guiding England back to the top of the Test rankings, not attempting to change his game when he should be at the peak of his career.

Suggesting that Cook is the right Englishman to open the batting at the World Cup is a view which simply can't be argued anymore. It's time to move forward, before another tournament passes by without England threatening to challenge for the title.

The longer Cook persists with this fight, the more damage he will do to his legacy. At 29, he probably gives little thought to how he will be viewed when he leaves the sport, but it's time for him to get back to what he does best.

Unless injury or another extended run of poor form intervenes, Cook will become England's leading run-scorer in Test cricket, and that's an achievement he could only have dreamed of as a youngster.

It's an achievement he deserves, but he must make sacrifices to be the England legend he is destine to become after proving his world-class ability to everyone in the 2010-11 Ashes series.

Leading the England ODI team no longer needs to be a part of Cook's future, but becoming England's greatest ever batsman in Test cricket still can be, if he admits defeat in one battle to make sure he's triumphant at the end of the war.