FOR – The man in place, so he will know the problems confronting the club and has already begun working on them. Obviously trusted by Roman Abramovich as he was chosen to fill the breach after the Russian owner decided to dispense with a Champions League-winning manager Roberto Di Matteo earlier this season. Experienced Premier League and European campaigner who reached two Champions League finals at Liverpool, winning one, and won the UEFA Cup and La Liga while at Valencia.
AGAINST – Chelsea's supporters detest him, even in a caretaker role, because of his association with Liverpool when the clubs were European rivals – and what he was purported to have said about the London outfit while he was in charge at Anfield. And the fans at Stamford Bridge have made this very clear.
Regarded as a coach who creates functional rather than exciting teams, perhaps due to obsession with tactics. Critics argue his European success with Liverpool was achieved with a team built by Gerard Houllier, and with a second-half recovery that owed more to the players than the coach.
On the evidence of the last few months, his fabled ability to get the best from Fernando Torres appears to have been over-stated.
FOR – The new Mourinho? Abramovich likes flavour-of-the-month-coaches and the fiery German is the latest after the way his Dortmund team took Manchester City apart in Europe while qualifying ahead of Real Madrid. Produces young exciting and domestically successful teams playing to a high tempo, despite a much smaller budget than rivals Bayern Munich.
AGAINST – No experience in England and limited success in Europe. It took Klopp two seasons before he turned Dortmund around. Time he would not be given at Chelsea, given the owner's previous propensity to fire. Methods seem to work best with young players and could clash with John Terry given his status.
FOR – Put himself in the frame last week when Swansea won 2-0 at Stamford Bridge to embellish an impressive first season in the Premier League. Shown tactical acumen by adapting the Swansea passing model to enable the team to be more direct, or more defensive as required. Success of Chico Flores and Michu suggests a shrewd eye in the transfer market. A wonderful player whose talent endures.
AGAINST – Managerial career promising but yet to live up to his playing record, which is stellar. Did well in Denmark but Brondby are a big fish in a very small pool. Elsewhere prospered at Getafe and Swansea, but not in the more demanding environment of Spartak Moscow which is more similar to Stamford Bridge.
FOR – Tactically sophisticated, good judge of a player, expert coach, steeped in both Spanish tiki-taka and, after playing in the lower divisions, English thud and blunder. Calm under pressure and able to lift his team after 9-0 and 8-0 defeats. Develops confident, patient, passing sides despite slim resources.
AGAINST – Yet to win any major honour – the only silverware he has won as a manager is the League One title with Swansea in 2008. Has no experience of coaching in European competition, all his top-flight experience is in fighting relegation battles and has a poor track record against the big clubs. Plus, if asked, he could deliver Abramovich a hugely embarrassing snub.
FOR – Brilliant tactician and man-motivator. Built the spine of the Chelsea team that has won three league titles, four FA Cups and the Champions League, albeit not all under his command. Has also won league titles in Portugal, Italy and Spain, and the Champions League with Porto and Internazionale. The man wins silverware wherever he goes. The man who toppled Guardiola's Barcelona.
AGAINST – Very high maintenance, as Roman Abramovich knows having sacked him in 2007 after three tumultuous years. If he returns, it is almost certain to lead to controversy before ending again in recriminations. Also linked Manchester United as successor to Alex Ferguson when he retires.