Antonio Conte concedes that Manchester rivals United and City will provide serious competition to Chelsea’s Premier League title defence.
The Blues swept to the English top-flight crown in 2016-17, with Conte’s first season at the helm seeing him restore domestic dominance in west London.
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He will, however, have Champions League football to contend next term, with European outings added to a hectic schedule.
Chelsea are also aware that the big spending of their rivals – with both United and City having broken through the £100 million barrier – means that the battle for Premier League supremacy will be even tougher in 2017-18.
Conte told reporters in Singapore as his side prepare to take in a pre-season meeting with Serie A giants Inter: “It is normal that every big team tries to reinforce their squad by bringing in quality players.
“That is what they have done [United and City]. For sure, next season in Premier League will be a huge challenge for us.”
Chelsea have strengthened themselves during the summer window, with deals done for Alvaro Morata, Antonio Rudiger and Tiemoue Bakayoko.
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Conte has also hinted that there may be more deals to come, saying: “We speak about the way to strengthen the team every day.
“We know which are the positions we need to strengthen.”
For now, though, the Blues boss is looking to integrate those already snapped up.
Morata is being eased into the fold following a big-money move from Real Madrid, with Conte saying of the Spain international striker: “He is working very well and is putting himself into every session.
“I think it is very good but it is important for him to have some time to adapt to our system. But I can see the will power in the player to do so.”
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Chelsea splashed out £70 million on Morata, but he has been overshadowed in pre-season outings to date by a man acquired 12 months ago – with Michy Batshuayi staking his claim to a regular starting berth with a flurry of goals.
Conte said of the Belgian: “I think Michy has worked very well in the pre-season and it is very important to score goals.
“It is important to adapt to our style of football and I'm happy when he scores. His confidence is also increasing. But it is important to continue to work very hard and keep improving.”
Chelsea will open their 2017-18 campaign with a Community Shield clash against London rivals Arsenal on August 6, before starting their title defence at home to Burnley on August 12.