Rudiger will be out of contract at Chelsea in the summer and negotiations over a new deal have been at a standstill for some time now.
The sanctions on Chelsea mean that the club will not be able to offer a new contract to the German at present and he is being courted by clubs such as Paris Saint-Germain and Juventus as well.
The centre-back has not ruled out joining another Premier League club and Manchester United are believed to be interested in snapping him up on a free transfer.
And Connolly feels the German would be a great signing for Manchester United as he is a massively underrated player in England.
He believes that Rudiger’s ability to play in multiple centre-back positions should suit the Red Devils as well and he would slot straight into the team if he moves to Old Trafford in the summer.
The former Premier League star said on Off The Ball: “I’ve seen Rudiger live a few times now.
“When you watch him live you come to appreciate what a good player he is. I think he is underrated.
“And I think he would slot into somewhere like Manchester United.
“He could play left and right centre-back and in a back three.”
Rudiger played a big role as Chelsea won the Champions League last season and has been a rock at the heart of their defence.
