Manchester United manager Ole Gunnar Solskjaer sees Chelsea as the biggest threat to his club's push for a first league title in nine years.
The Sun report that the United boss believes the return of Romelu Lukaku to Stamford Bridge can have a similar impact to Cristiano Ronaldo's return to United.
They also report that Solskjaer feels Ronaldo's arrival at Old Trafford makes the current United side better than the squad that won the treble back in 1999.
Solskjaer believes that strikers will make the difference in the title race this season and Manchester City and Liverpool's quality in the centre forward position is behind that of United and Chelsea.
The United boss feels that Lukaku is the only player in the title race that can have a similar impact to that of Ronaldo after both players returned to former clubs.
Lukaku returned to Chelsea from Inter Milan this summer for a club record £95million and scored on his second debut against Arsenal in August.
The Belgian is a player Solskjaer knows well, having sold him to Inter from United in 2019 in his first summer window as manager and will hope this does not come back to bite him this season.
Meanwhile, United re-signed Ronaldo after 12 years away from the club as the Red Devils chase their first league title since 2013.
United swooped to complete the £13.5million signing of the Portugal captain from Juventus after he had looked likely to join rivals Manchester City.
This leaves reigning champions City without a recognised striker other than Gabriel Jesus after they failed to bring in Harry Kane this summer.
Pep Guardiola's side were linked with Kane throughout the window but were unable to complete the signing after Tottenham Hotspur refused to drop their asking price.
The final team likely to challenge in the title race, Liverpool, also lack the same quality as Chelsea and United in the striking position with Roberto Firmino their primary centre forward.
The Brazilian forward scored just nine goals in the Premier League last season and is currently side lined with a hamstring injury.
All this gives Solskjaer reason to consider Chelsea as the main threat to his United side in the Premier League title race this season.