The Red Devils struggled to find consistent form in the Premier League last term as they ended up in a disappointing sixth place in the table.
However, Jose Mourinho did manage to lead Manchester United into the Champions League as they won the Europa League in his first campaign in charge at the club.
Manchester City, meanwhile, ended up third in the table in Pep Guardiola’s first campaign in charge at the club.
Chelsea will be hoping to defend their title after their impressive debut campaign under Antonio Conte at Stamford Bridge.
However, former Manchester United midfielder Giggs reckons that both of the Manchester clubs are poised to have a much bigger say on the title race next season, and is not sure Chelsea will be able to cope.
Speaking to talkSPORT, Giggs said: “It’s Jose’s second season with United. Last season they had the best squad and I think this year they’ve got the best squad again.
“They haven’t necessarily got the best XI, but their strength in depth is huge.
“And City; towards the end of the season away at Watford they had Gabriel Jesus, Leroy Sane, Sergio Aguero, David Silva, Kevin De Bruyne.
“That front five is scary…and Raheem Sterling wasn’t even on the pitch!
“It’s Guardiola’s second season in the Premier League, too, so they will be really strong.
“It’ll be interesting to see how Chelsea cope with the Champions League, but I can definitely see United and City contending for the title.”
Manchester United won the EFL Cup and Europa League in Mourinho’s debut campaign at Old Trafford.
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