Chelsea captain John Terry said Tuesday he was delighted by the way they had started their quest to regain the English title but insisted there was plenty of work to be done before the Premier League trophy was back at Stamford Bridge.

Table-toppers Chelsea are five points clear of second-placed Manchester City, the reigning champions, heading into the international break.

Chelsea have yet to lose in the Premier League this season, winning six out of seven games with their worst result a 1-1 draw away to City.

Sunday saw Chelsea see off London rivals Arsenal 2-0 in fine style and, with the club having been crowned champions when leading from the front during manager Jose Mourinho's first spell in charge, some observers are already questioning whether the Blues can be caught.

But with 31 league games remaining, centre-half Terry was not getting carried away.

"Clearly it (the title race) is not over," he said.

"Other teams have been in this position. It's nice to have the lead but when you're at the top everyone wants to shoot you down.

"That's the good thing about the Premier League and why everyone loves it.

"Teams are out to get us because we are at the top and playing well.

"The international break is here and we need to come back and maintain our form after that as well. It's very important we do that," the former England international added.

Chelsea are chasing a first Premier League trophy since 2010 -- the only time they have been crowned champions of England since double title-winner Mourinho's first spell in west London ended in September 2007.

The experienced Terry said it was essential to Chelsea's hopes they made the most of any stumbles by their title rivals.

"You're just hoping when you're at the top and have a five-point cushion and more on certain teams, a couple of them slip up again and that increases.

"If that happens, it's a lot of points to give up early on. All we can do is keep winning and wait for those teams to slip up."

Terry also said Chelsea were a more formidable side this season than last, when they finished four points behind champions City, following the arrival at Stamford Bridge of Diego Costa.

The Spain striker scored his ninth goal in seven Premier League games on Sunday, despite Portuguese boss Mourinho insisting the forward was struggling to train because of a hamstring problem.

Terry, however, played down suggestions Costa, signed for £32 million ($53.1 million, 40.4 million euros) from Atletico Madrid in pre-season, wasn't firing on all cylinders.

"I'm not sure where that's coming from," Terry said.

"He isn't showing that in training. He looks sharp, he looks angry, he looks aggressive.

"He's fit and that's the main thing. Diego has been a nightmare for defenders. He popped up with another great finish."

Former Arsenal captain Cesc Fabregas, whose superb pass set up Costa for his goal against the Gunners, has also proved a valuable addition to Chelsea's squad and an impressed Terry said: "When it's quiet and tight like that you need someone to open up the defence.

"He's not only shown it against Arsenal but from day one."