5 Biggest Issues Facing Chelsea Manager Roberto Di Matteo in Champions League

Roberto Di Matteo has his work cut out for him.

Di Matteo, 42, led Chelsea on an unexpected run to the UEFA Champions League title last spring as the club's interim manager. Now, after receiving the full-time gig, he faces a host of new challenges.

The Blues are expected to challenge for trophies on multiple fronts this season, and Di Matteo will have to deal with several issues both within and outside his squad.

Here are five of the biggest he'll face in the Champions League.

Ukrainian champions Shakhtar Donetsk are riding a hot streak that almost defies belief. Thirteen matches into the new Ukrainian Premier League season, Shakhtar have yet to drop a point.

Mircea Lucescu's team has played 13 matches, won 13 matches, scored 39 goals and conceded six times for a maximum points total of 39 and a mind-boggling goal differential of plus-33. Their lead over second-placed Dnipro stands at 12 points.

Armenian midfielder Henrikh Mkhitaryan is lighting up the scoring charts, having bagged 14 goals already. But this is far from a one-man team, as Alex Teixeira, Willian and others showed in Shakhtar's 2-1 home victory over Chelsea last week in the Champions League.

Make no mistake. Shakhtar are a strong team. They won't just challenge for qualification to the knockout stage.

They will challenge for the top spot in Group E.

Juventus have disappointed through the first three Champions League group stage matches. The Bianconeri have tied all three matches so far and needed a second-half equalizer to draw with Danish no-hopers FC Nordsjaelland.

Without suspended manager Antonio Conte, Juventus have been unable to reproduce their fine domestic form. But any team that prominently features Andrea Pirlo cannot be underestimated.

Juventus went through the previous Serie A season undefeated, and Pirlo remains an immense influence in the center of midfield. The Bianconeri are currently third in Group E with three points (one behind Chelsea), but Chelsea and Roberto Di Matteo would be foolish to ignore the potential threat posed by the Italian champs.

Chelsea are currently involved in another racism controversy, but this time the Blues are making the accusations.

After losing 3-2 to Manchester United over the weekend in a controversial English Premier League clash, Chelsea accused referee Mark Clattenburg of using racial slurs against two players.

To be clear, none of this is Chelsea's fault. Nobody at the club asked to be involved in another racism controversy after the John Terry-Anton Ferdinand saga of last season.

With that said, this new controversy could turn into an unwanted distraction, especially if it draws out the way Terry's incident did.

Roberto Di Matteo must be sure to keep his players focused on the pitch, rather than the investigation.

Chelsea won the Champions League last season and in doing so became the first London club to take home European club football's top prize.

That brought with it lofty expectations for this season. After another round of heavy investment in the squad this summer, Chelsea are expected to challenge for silverware on multiple fronts.

At the very least, the Blues are expected to qualify for the knockout stages of the Champions League. Considering the squad available to Roberto Di Matteo, that's a reasonable expectation.

But that doesn't mean there won't be any pressure, especially under an owner as notoriously fickle as Roman Abramovich. And once Chelsea qualify for the knockout stage—that is, if they do—every opponent will relish the chance to knock off the defending champions.

No pressure.

Apart from the loss to Manchester United, Chelsea have played stout defense in the English Premier League this season. Even accounting for the three goals scored by United (all of which came with captain and key defender John Terry suspended), Chelsea are tied for the third-best defensive record in the top flight.

The Blues have not had similar success defensively in Europe.

Starting with the UEFA Super Cup, in which Roberto Di Matteo's team allowed four goals to Atletico Madrid, Chelsea have conceded eight goals in four European matches this season (two each against Shakhtar Donetsk and Juventus).

That record will have to improve if Chelsea are to make another run.

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