The 30-year-old Belgian has refused to be carried away by the Citizen's impressive form.

Manchester United midfielder Marouane Fellaini has insisted that local rivals Manchester City are beatable despite their domineering start to the season. The Citizens have mounted a strong Premier League title defense by winning all their 13 games played so far.

Prior to the international break, a 3-1 victory over Manchester United at Etihad Stadium established a 12-point gap between Pep Guardiola's men and their city rivals. While the dream of winning the league for the first time in five years may be virtually over for the Red Devils, Fellaini believes the quest to securing the trophy may not be a stroll in the park for Manchester City either.

The Belgian midfielder's side currently sits in eighth position on the league log and faces a tough challenge climbing up with Liverpool and Chelsea also boasting an unbeaten record so far. For the top four battle, the likes of Tottenham and Arsenal are refusing to back down with a series of impresive performances and results.

"I remember when I arrived in England it was a top four, now it is a top six, so every year it is more difficult," the ex-Everton midfielder told Sky Sports.

"Next season we will see how it changes and in two and three years I think every year it is more difficult, the intensity is higher, so that's why the Premier League is attractive.

"Manchester City is strong, but I think they will lose. Ok, they are very good and they have good players but it's possible to beat them. We lost, but we have the second game at Old Trafford and we will see."

Fellaini also lauded the Etihad outfit for how they have been playing so far this season.

"They are very confident, all of them, they play good football, they play attacking football and they have a good dynamic," he added.