Chelsea Football Club is delighted to announce that Roberto Di Matteo has been appointed manager and first-team coach on a permanent basis.Chief executive Ron Gourlay says: “Roberto’s quality was clear for all to see when he galvanised the squad last season and helped the club make history, and the owner and board are very pleased he will be continuing his good work.”So finally, and perhaps with a hint of reluctance, Chelsea owner Roman Abramovich has agreed to hand Roberto Di Matteo the top job at Stamford Bridge…and all it took to persuade him was an FA Cup and Champions League double.The Russian oligarch took his time, sniffing around holidaying ex-Barcelona boss Pep Guardiola, before putting the Italian out of his misery.What Di Matteo achieved at the back end of last season was undoubtedly remarkable but the rest of the Premier League, particularly Chelsea’s immediate rivals at the top, might be breathing a slight sigh of relief at the news. The West London club are embarking on a huge rebuilding programme this summer, with Mirko Marin and Eden Hazard already on board and Portuguese forward Hulk set to sign this week. Such formidable talent in the hands of a manager of Pep Guardiola’s calibre would surely ensure Chelsea’s status as title-challengers.But Di Matteo’s record in the Premier League is questionable. The 42-year-old has the lowest Premier League win percentage of any Chelsea manager since Glenn Hoddle, with 45 per cent, and was sacked as West Brom boss in February 2011 after just 2 wins in three months.His Chelsea side also lost important games to immediate rivals Liverpool and Newcastle in the Premier League last term. Certainly his galvanising effect on the squad when he took over from Andre Villas-Boas cannot be underestimated, but Sir Alex Ferguson, Arsene Wenger, Roberto Mancini and co. may be breathing a tad easier tonight.