So much has been said over the past week about Carlos Tevez and so little about the man who shared last season's Golden Boot award with the Argentinian, but who could give him a lesson or two in what a footballer has to do to earn respect in complicated times. Dimitar Berbatov has accrued his over the past year, in the quiet, dignified way he has dealt with the many crushing disappointments that have brought us to the point at which his agent, Emil Danchev, is now willing to confirm that, yes, Manchester United are cutting him free at the end of the season.

It had been coming and, when it happens, it will be done with little fuss. A couple of lines on the club's website, maybe. Then Berbatov will politely put on his coat and show himself to the door, almost certainly at the rear of the building.

It has been an eccentric ride and it is not easy to make sense of how it has unravelled. Berbatov has exasperated and exhilarated in equal measure. He has played with our minds, bewitched us in the good moments and bemused us in the bad. Ultimately, however, we will have to consider that he has failed, at least in the sense that he is the most expensive player Sir Alex Ferguson has ever signed and he has plainly, irretrievably, lost the trust of United's manager. Yet the Berbatov story is such an unusual one that it is difficult to judge simply by ticking the boxes of success or failure.

He will be widely remembered, almost certainly, as a flop, yet 48 goals from 82 league starts and 24 substitute appearances is actually an improvement on his record at Tottenham Hotspur. Twenty of those goals came last season, when several colleagues, including Wayne Rooney, nominated him for the club's player of the year award. This season – however much his self-esteem has been scorched – he has still scored seven times in 10 appearances, half of them as a substitute.

These are the kind of statistics a striker would ordinarily cherish, but the inescapable truth is that Ferguson has clearly decided Berbatov is not cut out for the highest level. A theme has developed whereby Berbatov has been deployed against lesser teams, but stood down when the heat of the battle is less tolerable. The most staggering statistic is that he has not started against a top-six opponent for 14 months. Since arriving on the final day of the 2008 summer transfer window, he has been left out of 41 of United's 66 big games, meaning finals, semi-finals, European knockout ties, the Club World Cup and league matches against Arsenal, Chelsea, Liverpool, Manchester City and Spurs. He was not even on the bench for United's last two games and it would be no surprise if it was the same against Fulham on Monday.

What there has not been is a proper explanation, other than Ferguson telling Berbatov, according to Danchev, that he wants to "change the style of play of United, to put more speed in the game". A legacy, perhaps, of the beatings Barcelona have handed out to United in two of the past three Champions League finals. Berbatov's football could be set to a harp cadenza, whereas United operate to a different beat, more cha-cha-cha than slow-slow-slow.

In a game last year, one of Berbatov's team-mates took issue with him for not running hard enough. Berbatov pointed out that was the way he played and he didn't need to go faster. "You do at this club," came the reply, expletives removed.

All of which misinterprets the qualities that, sporadically, make Berbatov a formidable opponent – when his touch is at its most exquisite, it can make his audience believe he is on first-name terms with the ball. Magical, very often. Just maybe not often enough.

Berbatov will leave behind the sense that he lacks the one thing that can distinguish footballers at the very highest level – the force of personality to impose himself on the biggest matches. Exhibit A is last season's FA Cup semi-final, in which he spared Manchester City more times than he will care to remember. In the Champions League there were 22 games without scoring. He became the first United player since 1946 to score a hat-trick against Liverpool last season, but even that came with a rider, United's opponents being fifth from bottom at the time. Added to this are the long periods when his partnership with Rooney never shone as brightly as Ferguson was entitled to expect. There were only two occasions in their first season when one set up the other to score. They have flickered on plenty of occasions, but never truly ignited.

All of which has led us to the point at which Berbatov, in Danchev's words, now feels uncomfortable collecting his high salary from the club, an admission in keeping with his agent saying it is "not his style to start making scandals like Tevez". No interviews, no fuss, no briefing behind the manager's back, just the sense that he wished it had turned out differently, particularly if we remember last season's Champions League final, when United's top scorer did not even get a substitute's role and was so broken he never left the dressing room. After that, the only surprise is that the separation has taken so long to be confirmed.

Berbatov has drifted so far to the edges he is straying dangerously close to becoming one of football's forgotten men. On Friday, Ferguson held his first press conference since Danchev confirmed what everyone had suspected. Berbatov, the £30.75m man, did not warrant a mention.