Poor form at Stamford Bridge and inconsistency have damaged the west London side’s title challenge, probably beyond repair

André Villas-Boas’s diagnosis was brutally honest. Chelsea have not written off a title challenge just yet, their faith fuelled by the stumbles being endured by some of those above them, but there is an acceptance that, up to now, they have hindered themselves. They have not been what they once were. “What other teams see in our run of results is inconsistency,” said the Portuguese. “That has been our cancer this season. We are up and down, perhaps not in terms of performances but definitely in terms of results.”

This campaign has been littered with false dawns. Whenever Chelsea have threatened to inject real momentum and conviction into their challenge, they have stuttered. Their toils last month summed up the season to date: a victory over Manchester City that should have inspired was followed by a wasteful draw at Wigan; an encouraging performance at Tottenham Hotspur was undermined when Fulham and Aston Villa of lower mid-table were not subsequently beaten. Too many opportunities have been passed up. That the leaders are only 11 points clear of Chelsea feels surprising.

A visit of Sunderland, even a side whose confidence is bolstered by the Martin O’Neill effect, might normally represent a chance for the London club to reimpose themselves, but it now has the propensity to induce trepidation. It is the vulnerability at Stamford Bridge, an arena that used to feel impregnable, that has been most striking over the last 13 months and the Wearsiders, then under Steve Bruce, were the first to expose that fragility. Back in November 2010 they had arrived with memories of shipping seven in south-west London the previous season still fresh, only to deflate the locals with a 3-0 success that sent Chelsea hurtling head-first into Carlo Ancelotti’s often quoted “bad moment”.

That proved the first of five home defeats suffered in 23 matches, the last of which was endured against Aston Villa on New Year’s Eve. It is a sloppy record made all the more damning by the fact that only three league games had been surrendered in the previous 120, dating back to José Mourinho’s arrival in 2004. Dominance at home is so often used as a springboard, yet Chelsea have imploded too often where once they only thrived. That has hurt Villas-Boas most of all. Had Fulham and Villa been beaten, as the manager had convinced himself they would be in the wake of a series of away draws, Chelsea would be only six points from the top today.

There is a theme that runs through each of the three losses suffered at home this term; the hosts have ended up chasing victories in matches they believed had swung their way only to suffer on the break in the closing stages. Against Liverpool and Arsenal, Chelsea had clawed back deficits and sensed their opponents were wounded.

Villa might have been content to settle for the point they held, only to bite twice on the counter. Certainly, each of the visitors benefited from the home side’s willingness to over-commit, leaving a defence which is not as watertight as it was exposed and eventually exploited.

The ongoing pursuit of Gary Cahill, who should provide more resilience at the back, is a reflection of uncharacteristic weaknesses this season, though the manager’s defence of David Luiz and José Bosingwa, two perceived as the most error-prone, is unflinching.

“David is going to be one of the greatest central defenders in the world,” said Villas-Boas. “Why? Because of his characteristics: technical ability, anticipation and speed. I think he’s played fantastically well here, but sometimes people have misconceptions and a player has to carry that stamp for the rest of his life.” The observations of television pundits continue to infuriate the Portuguese.

“If everybody had perfect games, media pundits would have no jobs as there’d be no one to criticise. They’d have to find jobs in professional football, which is a little bit harder.”

Yet it is not only in defence that Chelsea have been found wanting. For long periods against Fulham and Villa, the home side had appeared aimless and devoid of zest and imagination, anxiety spreading from the stands to the players on the pitch. Even Portsmouth of the Championship held them until the interval on Sunday. It is on occasions such as these that the failure to secure a Luka Modric-type playmaker who can infiltrate mass defence and illuminate an occasion is felt so keenly. Games need not be chased if opponents are unpicked early and overrun.

Instead, Chelsea have been left all the more reliant upon Ramires’s energy through the middle and Daniel Sturridge’s eagerness on the flank, while forever trying to bring the intelligent Juan Mata into play. Those are fine weapons to have, but too often all three need to click for the team to prosper.

The manager will hope the late win at Wolves can at least inject confidence into the ranks to help kickstart a run of victories that will thrust the west London club closer to contention.

“We have a job to do to prove people are wrong to write us off,” said Villas-Boas. “We have to do that with actions on the pitch, not with words.” Starting against Sunderland he must pluck consistency from the ether if Chelsea are to trouble the leaders.

ChelseaAndré Villas-BoasPremier LeaguePremier League 2011-12SunderlandDominic Fifieldguardian.co.uk

• ‘We must carry on from here and keep that winning mentality’
• Midfielder says Chelsea have not been at their ‘very best’

Frank Lampard has called on Chelsea to rediscover their old spirit and pride after their 2-1 win away to Wolves on Monday. Lampard, who admitted that he was lucky to stay on the pitch after a horrific tackle on Adam Hammill, said: “It takes the big players in the dressing room and everyone collectively to stand up and make a difference which I think we did against Wolves.

“That has to be there. It’s something we’ve prided ourselves on at Chelsea for many years, it won us titles and won us a lot of things. It’s something we can’t lose. If you do lose that then you can’t be at the top.

“Sometimes it takes a result like this [to change a team's mentality] – but we must carry on from here and keep that winning mentality, that fight and that desire.”

Lampard, who scored the winning goal against Mick McCarthy’s side, also conceded that Chelsea have not been at their very best since wins over Valencia in the Champions League and Manchester City in the league: “If you don’t play well enough then you don’t get results, it’s difficult now, Blackburn [Rovers] against [Manchester] United, Sunderland against [Manchester] City, teams aren’t mugs. They’re all set out very well and if you’re not at your very best you won’t win games. The brutal fact is that we haven’t been at our best since beating Valencia and Manchester City.”

The England midfielder paid tribute to the Chelsea fans who have continued to support him through what he described as “tough times”.

“These fans have been amazing for me for the last 11 years, from the moment I joined the club, they’re part of my life now. When you have certain tough times in your career, this isn’t the first – and it might not be the last – they’re always there, and the ovation they gave us at the end was reciprocated by me. They know how much they mean to me and it’s the same both ways.”

Frank LampardChelseaIan McCourtguardian.co.uk

Having reached the Champions League knockout phase, the young Chelsea manager now faces critical challenges at home

It is hard to imagine the little jack-in-the-box, that bundle of nervous energy, getting much of a night’s sleep after a match. Now that his Chelsea team have at last passed a test of character, he could rest a little easier. For the next five days, until he picks his team to take on Manchester City, André Villas-Boas can allow himself a long deep breath and take stock about what has been one heck of a learning curve.

In securing their Champions League progress, Chelsea won consecutive games for the first time in almost two months. They now face a period which is critical to the Villas-Boas masterplan. Three of their upcoming four games take in City, and derbies at Tottenham and home to Fulham (London opposition having been particularly troublesome this season). If they can negotiate all that without trauma, they then have a run of fixtures which could hardly be better designed to give them scope to regroup and press on: a sequence of Aston Villa, Wolves, Sunderland, Norwich and Swansea take them through to February, by which time the Premier League landscape could look a little different.

So, too, could the Chelsea squad. With a couple of well documented departures on the cards in the January window, it will be fascinating to see what kind of recruits arrive. The burning question, of whether Roman Abramovich has been convinced to give his coach carte blanche to identify which reinforcements he wants, remains moot. Will it be another January where a £50m striker and a £21m Brazilian maverick to play centre-half will be the order of the day? The answer will tell us as much about Villas-Boas, and where he stands in the great scheme of things, as Abramovich.

If there is a battle with the dressing room to be won, then Villas-Boas has at least offered some early shots. Omitting, at various stages, some of those José Mourinho defined as his untouchables – John Terry and Frank Lampard, plus Fernando Torres and now the exclusion zone around Nicolas Anelka and Alex – has obviously had an effect on the dressing room. But what emerged out of the friction at a fiercely focused Stamford Bridge on Tuesday night promised that changes are afoot and not necessarily for the worse.

It is not that he has had anything as dramatic as a Carlos Tevez moment, but in a more subtle way he has challenged players who have been, or might expect to be, highly influential. That said, it was significant to see the old guard – notably Terry and Didier Drogba – leading the troops with impassioned speeches during the pre-match warm-up.

For all that Villas-Boas is detailed to put in place a dash of the flamboyance that Abramovich desires, it was intriguing to see that in a moment of need, Chelsea reverted to type. If you half closed your eyes as Valencia had the life squeezed out of them, it could have been vintage Mourinho. Petr Cech infallible in goal, a solid foundation in front of him that took no risks, and sudden counterattacks led by a powerhouse performance from Drogba to do the damage.

Transferring that resilience, cohesion, and calibre of performance into a maximum pressure Premier League game is the next big test for Villas-Boas. It took a matter of minutes after Europe had been taken care of for him to flick his mind towards a duel with the Premier League’s pace setters. City will visit a steadier looking Stamford Bridge on Monday night.

Chelsea’s young coach only recently tasted victory against one of the English game’s top brass this season, last weekend’s flourish at Newcastle ending a run of defeats to Manchester United, Arsenal, and Liverpool twice. He has been adamant that a cavalier approach would not be sacrificed. But the consequences of a more conventional performance against Valencia might just persuade him otherwise.

André Villas-BoasChelseaChampions League 2011-12Champions LeagueAmy Lawrenceguardian.co.uk