The Baggies summer signing returned from a calf problem against Nottingham Forest towards the end of pre-season, only to pick up a knee injury in the City Ground encounter that has kept him sidelined ever since.
"Joleon is actually going to go to the States and do a fitness routine over there with people I know and who I've worked with before at Everton," said the Albion boss.
"This is just a pre-season programme for him with people who have also worked with him before.
"There's no concern, there was just a feeling that it might be the best approach for him at this moment.
"The plan is that he will come back from that absolutely ready to go and we can have him for the following week ready to train with the lads."
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