Roberto Mancini insists he will solve Manchester City’s problems quickly as the English Premier League champion heads into a crucial clash against Sunderland on Saturday.

City’s sluggish start to the season has been a sobering experience for Mancini, whose team won its first title in 44 years last season but could go into the international break seven points adrift of leader Chelsea.

Mancini has not fielded the same starting line-up twice all season as the City manager tinkers with a team that has won only three of its nine matches in all competitions and has conceded 16 goals in that run of games.

After City narrowly escaped with a 1-1 draw despite being outplayed by Borussia Dortmund in the Champions League on Wednesday, Mancini said that he knew what was wrong with his expensively-assembled team.

But while it is still early days in the title race, he doesn’t have long to put things right.

City is already four points behind pace-setter Chelsea and another poor result against Sunderland would be a major blow to its hopes of retaining the title.

While City thrived as challenger last season, Mancini admits the team found it harder to cope with sides raising their game when they come up against the champion.

Spanish midfielder Javi Garcia sustained a hamstring problem against Dortmund and could miss out against Sunderland, while the game is likely to come too soon for right-backs Micah Richards and Maicon, who have both been struggling with ankle problems.

Sunderland was the only visiting side to deny City victory at home in the league last season, courtesy of a dramatic 3-3 draw in March, meaning the Wearside club took four points from the Premier League champion after beating it 1-0 at the Stadium of Light in January.

Its hopes of emulating those results would be improved if Adam Johnson delivers on his first appearance against City since the England midfielder’s £10 million move to the north-east in August.

Meanwhile, Sir Alex Ferguson has had nine months to come up with a plan to combat the threat of Demba Ba and how Manchester United cope with the red-hot Newcastle United striker on Sunday could define its Premier League season.

The Senegalese bullied United’s injury-hit backline in Newcastle’s 3-0 victory on a windswept night at St. James’ Park in early January, and will surely be licking his lips at the thought of testing a defence which has been uncharacteristically sloppy so far.

Third-placed United has leaked nine goals in six league games, including three in last weekend’s surprise home defeat by Tottenham Hotspur.

Injury has again robbed the Old Trafford side of Nemanja Vidic’s steadying presence for the foreseeable future, and now Ferguson has injury worries over Vidic’s fellow centre-back Jonny Evans.

Even though it conceded a sloppy early goal to fall behind, Ferguson praised his backline for a resolute display in the 2-1 Champions League victory in Romania over Cluj on Tuesday.

With the imposing Ba, the Premier League’s top-scorer with six this season, and strike partner Papiss Cisse awaiting, Ferguson can ill afford to lose Northern Ireland international Evans.

The defender is battling to shake off a dead leg and was replaced late on by young centre-back Scott Wootton against Cluj.

Wootton made his debut in United’s 2-1 League Cup victory over Newcastle at Old Trafford last month. Cisse notched up his only goal of the campaign in that defeat, a match which Ba played no part in.

Mirallas praised

Second-placed Everton, three points behind Chelsea, makes the short trip to Wigan Athletic on Saturday with manager David Moyes hailing the impact of Belgium forward Kevin Mirallas.

The Goodison Park side’s acquisition of Mirallas from Greece’s Olympiakos was one of the more unheralded signings of August but the 24-year-old has surprised Moyes with how quickly he has settled on Merseyside.

A tasty London derby is in store at Upton Park in Saturday’s late kick-off when Arsenal aims to check West Ham’s United’s bright start.

Arsenal manager Arsene Wenger was less than enamoured with his side’s defending in its first defeat of the season last weekend at home to Chelsea and could decide to bring back Per Mertesacker to combat the threat of West Ham’s big frontman Andy Carroll.

Wenger deployed Laurent Koscielny instead of the previously impressive Mertesacker against Chelsea, a move that was less than successful, and the Frenchman also started the 3-1 Champions League win over Olympiakos Piraeus on Wednesday.

Fit-again England centre-forward Carroll believes West Ham — one place and two points above Arsenal in seventh — can cause the visitor plenty of problems.

Chelsea welcomes struggling Norwich City to Stamford Bridge on Saturday.

Liverpool, winning at the sixth attempt with a five-goal romp at Norwich last weekend, welcomes Stoke City to Anfield on Sunday.

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