O'Shea is thought to be winning the race to be available, and it would not be a surprise to see the strugglers again line up in a 5-4-1 formation.
Callum Robinson came off the bench to score twice in last weekend's 5-2 victory at Chelsea, and the 26-year-old could now be handed a position in the starting XI, potentially at the expense of Matt Phillips.
Conor Gallagher is also available, with the midfielder missing out against his parent club last weekend.
Okay Yokuslu could drop out of the midfield to allow Gallagher to return, while there will be another start in a forward area for Matheus Pereira, who also netted a brace against Thomas Tuchel's side last time out.
West Brom possible starting lineup: Johnstone; O'Shea, Bartley, Ajayi; Furlong, Gallagher, Maitland-Niles, Townsend; Robinson, Diagne, Pereira
> Click here to see how Southampton could line up for this contest Watch the Sports Mole Football Shorts prediction for this game below:
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