ALBION defenders Lewis Dunk and Shane Duffy have their work cut out against Manchester United – who ever Jose Mourinho throws at them.

That is the warning from Andy Ritchie, who played for both clubs, as doubts surround the make-up of Mourinho’s strike force for Sunday’s trip to the Amex (4pm).

The Dunk-Duffy partnership will be key to Albion’s hopes of their first Premier League points of the season and a repeat of the 1-0 win against United in May following the disappointing start at Watford.

Lukaku missed the May meeting through injury but scored one of his 38 goals last season against the Seagulls in the FA Cup at Old Trafford.

He came off the bench after his World Cup exertions with Belgium in United’s opening 2-1 win against Leicester at Old Trafford, when Mourinho started with Marcus Rashford and Alexis Sanchez and also had Anthony Martial among the substitutes.

Former striker Ritchie said: “Dunk and Duffy just seem to roll off the tongue and they are probably the closest I would say in the Premier League to maybe an old school pairing at centre-half.

“The two of them I think are becoming a little bit folklorist, a bit like Bruce and Pallister, people like that.

“They would know the enormity of playing against him (Lukaku), because he is an absolute beast.

“You never get a minute’s rest. You know you are going to be in a physical battle. He wants to back into you, because he likes to be able to turn people.

“They will know they’ve got a real game on their hands if he plays.

“Then you look at the flip side of it and if Martial or Rashford are playing up there they’ve still got things to think about.

“Rashford’s pace, he will run them and do other things that Lukaku won’t, although Lukaku is just as fleet of foot.

“Martial again would pose a different threat. I think he (Mourinho) might just start with either Rashford or Martial again.

“He could even put Sanchez down the middle. He has in pre-season. you never know, it’s a guessing game.”

Ritchie will be radio co-commentating for MUTV on the clash between two of his old clubs.

United are seeking to avenge only their second defeat by Albion in 19 clashes between the clubs in all competitions.

Ritchie said: “The manager will want to continue with a good start. They just about deserved the win the other night, played very well second half in terms of controlling the game.”