Acid test for Chelsea chief

The manager was a quiet insurgent last year, happy to surprise his way to the Champions League title, doing what no Chelsea manager had done before. This year he is in a different position. The Italian cannot be an outsider with those medals around his neck. So he is on a pedestal, more confident in his pronouncements but there to be aimed at.

Tonight Shakhtar Donetsk come to the Bridge, knowing that an away win will leave Chelsea with a huge battle to stay in the Champions League. On Sunday it is Liverpool. Both visitors will be desperate to beat Chelsea, as teams play beyond themselves to knock them down. Chelsea have won one of their last four games in all competitions, and even that needed extra-time against a Manchester United reserve side.

That aside, they were well beaten by a fine Shakhtar display in Ukraine, outgunned by United in the league and then pinned back by Swansea last Saturday.

This is going to be a difficult few days for Di Matteo. So much of his success at Chelsea so far is down to his ability to calm stormy water. Andre Villas-Boas was a destructive, dynamic force, eager to tear down and rebuild. Di Matteo is gentler, and by renewing the unity and focus of the squad he helped deliver the FA Cup and the Champions League title.

But Stamford Bridge remains a maelstrom of controversy. In one four-day spell, Chelsea lost a controversial five-goal game to Manchester United, complained about alleged racial abuse by Mark Clattenburg, won a drama-laden nine-goal game against United, and saw one of their supporters shame the club with what looked like a racist gesture.

Last season, Di Matteo wanted to slow down those currents of controversy which shape English football. This year he seeks to master them. Alex Ferguson had said he disbelieved the accusations against Clattenburg. This Di Matteo would not just cede control of the news cycle: he swung back at Ferguson, advising him not to talk about other teams, and adding that the United manager was favoured by officials.

There is a confidence that comes with being European champion but also a price. After beating Chelsea so well -- 2-1 is a poor reflection -- in the Donbass Arena last month, Shakhtar will be all out to do the same again tonight. The Ukrainians are a very good team but have yet to win in England: if they manage it here, they will qualify for the last 16. It would also leave Chelsea fearing a defeat in Turin that could knock them out -- Juventus had the better of the draw in London.

Then, on Sunday, Liverpool come to Stamford Bridge. This fixture has lost some of its lustre but is always an important fixture to the Reds. And if Luis Suarez is on song then Chelsea's back four, even with John Terry back, could be disrupted.

Terry should play this evening, and his four-game domestic ban is now over. His presence must help to bind together a struggling back four. Terry, still the captain, is a reminder of how Di Matteo has been able to navigate through crises and keep the team successful.

The problem is, there is no end in sight to these various storms. Opponents are now all set on bringing Chelsea down.

His is a high-wire act and his balance and his judgement have to be perfect.