Diego Costa
Diego Costa has scored 11 goals in 14 league appearances for Chelsea this season AFP/Getty Images

Former defender Gary Neville says Chelsea have a "massive chance" of winning the Premier League title if they can keep Diego Costa and Eden Hazard fit.

The Blues fought back from a goal down to beat Manchester City 3-1 at the Etihad Stadium, courtesy of goals from Costa, Willian and Hazard.

The result extended Chelsea's winning run in the league to eight games and stretched their lead at the top of the league table to three points.

Speaking on Sky Sports, Neville said Chelsea's title challenge rests on the form and fitness of key men Costa and Hazard.

"They are in with a shout [of winning the league]," the former Manchester United defender said.

"They have title winners in that dressing room and I think the ones that have won the title before will be thinking, 'This is good.'

"Costa and Hazard have to stay fit, that's the big thing because the drop in quality behind those two is enormous.

"They look really up for it. Hazard looks brilliant, Costa looks brilliant and if they can keep those two fit, they are in with a massive chance.

"There was a devastation about Chelsea today. I am not going to hand Chelsea the title now, it's far too early for that, but when I think of teams that have won the league over the years, I think of teams that are capable of attacking in four or five seconds."

Neville also spoke about the mass brawl between City and Chelsea players at the end of the match that resulted in both Sergio Aguero and Fernandinho getting sent off.

Aguero was dismissed for a reckless lunge at David Luiz, while midfielder Fernandinho was shown a red card for clashing with Cesc Fabregas.

"We talk about players defending the shirt, the passion, and defending each other as teammates. If one of your teammates has been wronged in a tackle, you expect your teammates to steam in and get about them," Neville said.

"I'd expect disappointed players, I'd expect hurt players, I'd expect players to react when things don't go their way and today I saw all that."