The challenges of Chelsea

Salomon Kalou, centre, trains with his Chelsea teammates in London yesterday.

If football is a game of two halves, then Chelsea's is a season of three thirds. Unstoppable at the start and finish, unconvincing in the extreme in the middle, theirs is becoming the most improbable challenge of all.

Momentum has been lost and regained in swings of dramatic dimensions. Having taken 28 points from their first 12 games, Chelsea stumbled during the extended slump Carlo Ancelotti described as "our bad moment", 14 games producing a mere 17 points.

Then they were rejuvenated, resembling the irresistible force who finished last season with a flurry of goals. Their last seven games have produced 19 points. Carry on in the same vein and they may yet remain champions.

They are the Premier League's new yo-yo team. Having gone from first to fifth, they have bounced back up to second. Ruled out of the title race by no lesser authority than Ancelotti himself, they have emerged as Manchester United's main challengers.

They do so to a bizarre backdrop. Their revival has come despite, not because of, the British record signing of Fernando Torres, whose 13-game, 725-minute Chelsea career is yet to yield a goal. Moreover, a manager who merits rather more credit for the turnaround is likely to depart. An admirably phlegmatic Ancelotti is unsure where his future lies.

The chances are that, unless United falter, recent results will count for nought. Roman Abramovich appears a keen believer in the former Liverpool manager Bill Shankly's maxim: "If you are second, you are nothing."

So Avram Grant can testify: the West Ham United manager finished as a runner-up in three different competitions in his sole season at Stamford Bridge and was dismissed.

He is now second from bottom in the Premier League, a different kind of nothingness but one which does little for his chances of continued employment.

That Scott Parker has been named Footballer of the Year by England's Football Writers Association while West Ham languish in the relegation zone shows the scale of underachievement at every other level of the club.

With Parker sidelined today and fellow midfielder Gary O'Neil ruled out for the season with an ankle injury, these are two clubs heading in opposite directions.

Grant's Hammers have lost their last three games and, with their next two matches away against top-four opponents, the manager's target of a further nine points to stay up is increasingly ambitious. Chelsea, for different reasons, have even less leeway.

A mutual need for points should increase the animosity. When west London meets east, it is one of the capital's more complicated rivalries.

A decade since Frank Lampard traded Upton Park for Stamford Bridge, he remains a figure of hate among the West Ham supporters.

Grant himself may be held in higher regard by his former players than his current charges.

While he revisits his past, Chelsea are repeating theirs. "Our shape is good. The players are comfortable with that," Ancelotti said. Minus Torres, they have flourished by reverting to 4-3-3.

Didier Drogba is performing with purpose and potency, even if his manager is pondering using him as a substitute today. "It wouldn't be easy to leave Drogba out," Ancelotti added.

"It might be a good solution to give him the last 30 minutes of the game because he's fresh and fit. We started with Torres against [Manchester] City. We won the game when Didier came on."

It is part of the desperation to end the £50 million (Dh295m) man's drought.

"To score one goal, for him, could be the best medicine," Ancelotti explained.

But the more logical move would be to persist with Drogba and the shape and the system Grant knew from his time at the club.

It is classic Chelsea, and it is likely the blueprint will be ripped up in the summer. Like much else at Stamford Bridge, it can defy belief.