Maybe somebody slipped a lump of Kryptonite into his tea.

Maybe, after flying so high last season, Superman was bound to come to earth at some point.

Or maybe Stevie Ireland and Roberto Mancini are just not a good fit.

Ireland's fade-out from the first name on the City teamsheet to an increasingly marginalised man is one of the great mysteries of the season.

And whether the slide in the 23-year-old midfielder's fortunes at City is a slip, or is an inexorable rush for the Eastlands exit door, remains to be seen.

The romantics at City would like to believe the old maxim of form being temporary and class permanent, and that Ireland will revive a currently unconvincing team and gloriously lead them into the Champions League.

Spark

But at present, it is hard to see where Ireland fits into the picture. On Sunday at Sunderland, the situation appeared to be crying out for the man who last season had been the fans' player of the year, and the first City player to be named Greater Manchester player of the year.

A goal down, and packed with defensive midfielders, the Blues needed a spark of invention, someone who could arrive from deep and nick a goal, someone to feed the starved talent of Carlos Tevez.

Ireland sat on the bench, frustrated and hopeful, and there he remained, as Mancini threw on Patrick Vieira to try to give his team shape and purpose.

Indeed, Ireland has only played two full matches under Mancini, although his season has been interrupted by injury.

There is a deep, and bitter, irony to the fact that Ireland's City career now appears to be at a crossroads, just eight months after it appeared to be moving into the fast lane.

Ireland had his problems as a teenager, occasionally struggling to come to terms with his new-found status after joining City as a wide-eyed 15-year-old.

Last season he showed that he had reached maturity, both as a person and a footballer.

He had settled in nicely to a comfortable superstar's lifestyle, complete with glamorous partner, flash cars and a mansion in Prestbury.

And his work for Francis House Children's Hospice showed that there was depth to the character, and a heart to match his football brain.

His dedication to his trade was, and is, unswerving. While others head for Miami or Sardinia, Ireland heads for the hills above Glossop for a punishing summer training regime of running and martial arts.

Some felt he was pushing himself too hard in the pursuit of perfection, a belief which appeared to be borne out when he suffered dizzy spells and a heart scare during a Carling Cup win over Fulham in September.

Both Ireland and City were adamant that his fitness regime was unconnected to the problem, and Ireland was soon back in action.

But he failed to hit the same kind of form which made him such a favourite last season, when he netted 13 goals.

And then manager Mark Hughes also felt Ireland needed some competition, and was actively seeking a creative midfielder when the axe fell on him in December - Scott Parker was a name being whispered loudly around the corridors at City.

But it was the appointment of Mancini which has truly cast a shadow over Ireland.

He played in the first two games, wins over Stoke and Wolves, but picked up a hamstring injury in the latter - and has failed to pin down a regular place since returning in the FA Cup win at Scunthorpe.

In the last two matches, at Sunderland and Chelsea, Mancini has adopted a safety-first approach to team selection, plonking the solid slab of Pablo Zabaleta, Nigel de Jong and Gareth Barry in midfield, and opting for a couple of wide men to support Tevez.

The strategy has had mixed results, with an exhilarating victory at Chelsea and a scrambled draw at Sunderland.

The Italian is something of a Ronseal manager - he likes players who do exactly what it says on their tin.

He likes defenders who defend, strikers who score goals, wingers who create them, and midfielders who, first and foremost, stop the other team from playing.

Talent

Ireland does not fit in. He is something of a maverick, and that kind of player always lives a knife-edge existence.

When things go well, a free-ranging talent pops up, scores goals, makes them for others, and earns the adoration of the crowd.

But when things get tight, results need to be ground out and the manager values substance over style, the maverick player becomes a luxury item.

Whether or not that means Ireland will be on the move in the summer remains to be seen. And whether Liverpool and United - both linked with him recently - would want a player who has not yet nailed down a City place, is also dubious.

For all the accusations of negativity, Mancini has shown he is not afraid of pulling bold strokes.

Maybe he is reserving Ireland's talents for the run-in, when six of City's last nine matches are at home, where Mancini and his team are much less inhibited.

With Spurs and Liverpool threatening to hit the accelerator, City could do with a hero … why not make it a superhero?