Manchester City striker Stevan Jovetic believes his side's thrilling UEFA Champions League win over Bayern Munich last month could have made all the difference in the bid to retain their domestic crown.

Since Sergio Aguero's hat-trick sunk the Germans at the Etihad Stadium, City have put a tough series of top-flight results behind them and earned emphatic away victories at Southampton and Sunderland.

Aguero was on target twice more in the 4-1 win at the Stadium of Light on Wednesday night and Jovetic says it is plain to see his side are playing with renewed confidence after pegging back leaders Chelsea to just six points.

Jovetic told City's official website: "Honestly in the Champions League we have not played well this season but the game against Bayern helped us a lot.

"Now we are in a very good moment but we must continue like this because we are playing every three days and that can change, so we need to give 100 per cent in every game and be behind Chelsea and expect them to drop points.

"We have more confidence because we had some bad times two or three weeks ago when we didn't play so well."

City boss Manuel Pellegrini is hopeful captain Vincent Kompany will be fit to return for next week's crucial Champions League clash with Roma after missing out on the trip to the north east with a hamstring injury.

Kompany is also definitely out of Saturday's clash with Everton and it was initially feared he could be sidelined for longer, but initial scans suggest the injury is not as bad as was first feared.

Meanwhile, Sunderland boss Gus Poyet has injury problems to add to issues of fatigue as he prepares his side for their third big game in a week at Liverpool at the weekend.

Poyet's men are clearly struggling after back-to-back clashes with Chelsea and Manchester City and Steven Fletcher's substitution with an apparent back injury 55 minutes into the Stadium of Light clash will give cause for concern.

But there could be better news on midfielder Adam Johnson who missed Wednesday night's game against his former club with a minor injury which should clear up for the trip to Anfield.

Poyet said: "Adam had a muscle problem at the end of the game (against Chelsea) and he was very close (to playing) but it was not enough."

Johnson was replaced by another former City man, Will Buckley, who admitted the Black Cats squad are feeling the strain of their hectic and high-profile fixture pile-up.

Buckley told his club's official website: "Obviously it was a massive effort on Saturday and a good point but it does take it out of you, and hopefully we can look ahead now and have a good performance against Liverpool.

"We don't like to dwell on bad performances and results so we will look to get it out of our system as soon as possible. We need to find a bit of the performance against Chelsea and take it to Anfield and do a bit better."

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