Chelsea have been in improved form in recent weeks under Antonio Conte as they look to try and defend the title they won under the Italian manager last season.
Both of the Manchester clubs have also started the season strongly as the Premier League title race looks set to be one of the closely-contested in years.
Chelsea have won the Premier League in two of the last three seasons and Conte will also be hoping to steer the Blues to Champions League glory this season.
And the former Chelsea man believes that the west London side have proved in recent weeks that they will be among the main contenders for the title this term.
Speaking to the Daily Star about the title race, former winger Nevin said: “I thought the title race would be between United and City before the season and I didn’t think I would be putting Chelsea in that bracket.
“But with the players that Chelsea have added, particularly at the end of the transfer window, [Alvaro] Morata has hit the ground running and [Tiemoue] Bakayoko is clearly miles good enough to cover [United signing Nemanja] Matic, I’m now beginning to think that Chelsea could be up there.
“[Danny] Drinkwater is a great addition. [Davide] Zappacosta is absolutely magnificent, far better than I would have thought.
“I wasn’t sure where the cover was all over the field [earlier in the summer] but now I look at it and they are fine.
“[Andreas] Christensen is definitely good enough. And [Michy] Batshuayi, when you look at his minutes to goals ratio, it’s mental, it’s extraordinary.
“You look around the squad and think they do have a lot of options. I think it’s a good argument that the title race will be between them three.”
Chelsea return to Premier League action after the international break with a trip across London to take on Crystal Palace on Saturday 14 October.
Manchester United, meanwhile, will switch their attentions towards their crunch Premier League clash with Liverpool at Anfield after the forthcoming international break.
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