West Ham manager Sam Allardyce has taken three defenders on trial with a view to strengthening the Hammers' back line.
Unattached trio John Mensah, Mikael Silvestre and Anthony Vanden Borre are all available on free transfers after leaving Lyon, Werder Bremen and Genk, respectively, in the summer.
All three have Premier League and international experience and their unattached status allows them to be signed after the official transfer deadline.
However, Allardyce stressed that he will reserve judgement on each of them until after he has had a chance to see them in training.
"They have been training with us but there is no decision on whether we will be pursuing their services or not at this moment in time," the Hammers boss told Sky Sports.
The Irons added George McCartney and James Collins to their defence this summer, after letting Abdoulaye Faye and Julien Faubert go from their promotion-winning team.