Manchester United legend Ryan Giggs has questioned whether Chelsea will be able to juggle their domestic duties with European football during the upcoming campaign.

Antonio Conte's side stormed to the Premier League title in record-breaking fashion last season, winning an unprecedented 30 matches to finish seven points clear of Tottenham Hotspur.

However, they did not have European football to contend with then, and Giggs believes that both Chelsea and Spurs - who are yet to make a single signing this summer - may need strengthening if they are to challenge for the title again.

"You can't ignore Chelsea because of their quality, but have they got the squad to balance defending the Premier League and European football? I'm not sure," he told Sky Sports News.

"Tottenham have a really exciting squad and a great manager in Mauricio Pochettino, but everybody is asking whether they can continue to match sides without signings.

"I think they need a couple, not to improve their starting lineup but to make the squad better, while they've also got the Wembley factor, so they really need to get off to a good start."

Giggs also backed Manchester City as his favourites to win the title next season.