André Villas-Boas is still confident he will be allowed to oversee the second leg of Chelsea's Champions League knockout tie against Napoli next month, although the manner of Tuesday's chaotic defeat at Stadio San Paolo has spread alarm among the club's hierarchy.

Roman Abramovich, who was not in Naples, was understandably unimpressed with the 3-1 reverse in Italy. The oligarch has resisted making a quick-fire decision on the 34-year-old's future up to now, but his patience has been sorely tested by a slump that has led to only four wins in 14 games and caused Chelsea to slip out of the Premier League's top four.

Villas-Boas has benefited from steadfast support in Abramovich's long-term "project", but that faith is being eroded while the current campaign unravels, and an immediate improvement is required to prolong his tenure.

The availability of Rafael Benítez, who won a European Cup with Liverpool in 2005 while he was overseeing a period of transition after Gérard Houllier's tenure, has not helped Villas-Boas. There are suggestions that the Spaniard could replace Villas-Boas initially until the end of the season, charged with securing Champions League qualification, while Chelsea consider their longer-term options.

Benítez had expressed a desire to take the job at Stamford Bridge last summer following the dismissal of Carlo Ancelotti and is aware of some level of interest in his services, but he is understood to be reluctant to consider what would effectively be a temporary position until May. He would push for a deal that would stretch through at least to the end of next season as he seeks a return to management some 14 months after being sacked by Internazionale.

Villas-Boas is due to give his weekly press conference at Chelsea's Cobham training base on Thursday lunchtime, with the club officially insisting it is "business as normal". Yet the ramifications of the loss to Napoli, and the manager's risky team selection, are all too clear.

The omissions of Ashley Cole and Frank Lampard from the starting line-up prompted angry outbursts from both players before kick-off. Details have emerged since that the pair had been particularly vocal in their criticisms of the management in a clear-the-air meeting at the training ground last week. The England left-back is understood to have openly questioned whether the team's tactics could win the club trophies.

Neither player will be sanctioned by the club for the show of dissent in Naples. Villas-Boas conceded in the immediate aftermath of the loss that although his selection had been for "technical" and tactical reasons, both England internationals had been disappointed because they felt they "could have helped the team", before adding that it was a decision they "had to accept and move on".

Lampard and Cole remain available for selection, with Bolton Wanderers due to visit Stamford Bridge on Saturday, but it appears unlikely that their relationship with the manager can be healed.

Should Villas-Boas instigate a revival and claim the fourth Champions League qualification place, thereby prolonging his stay, there would be implications for both in the summer. Cole is one of the few members of the old guard who would still command a relatively healthy fee. Lampard, however, has entered the final 18 months of his deal and is unlikely to put up with a bit-part role for a further season.

The 33-year-old would concede that any new coach appointed in the summer might also regard him as no longer an integral part of the team, increasing the likelihood that he will move on. Paris St-Germain, managed by Ancelotti, retain an interest and LA Galaxy would offer an intriguing alternative destination.

There was an acknowledgement of the dissent in the dressing room on Thursday from Branislav Ivanovic, who was signed by Avram Grant in 2008 and has worked under four managers in as many years since. "These things always happen when you are losing," said the Serbia international. "They come out. But this is more about Chelsea. That's more important than the relationship between managers and players. A lot of things are wrong and, for me, this is the hardest moment during my four years here. We haven't won a lot of games, and the confidence is not in the best way.

"I can't say he [Villas-Boas] will stay, but we have to be focused on our jobs. The manager who decides who plays is doing his job. We have to do our job. His is a hard position, very difficult, so of course it is important we stay together because our squad is not doing what people expect of us." They will be without John Terry for up to two months, with the club still evaluating the results of an exploratory arthroscopy on the England defender's knee.