West Ham have asked about Paris St Germain defender Thilo Kehrer as they close the sale of Issa Diop to Fulham.
Diop, who Moyes said had not made himself available for recent games, is being sold to Fulham for around £15m plus add-ons.
It leaves West Ham short on defenders with Craig Dawson nursing a thigh strain and Nayef Aguerd out for months.
PSG want around £17m for German international Kehrer, 25, who can also play at full-back.
Kehrer is extremely quick as well as a good passer and is regarded by many as a potenitally world class player.