The 29-year old Greece international has been starring for Leganés in La Liga this season, playing in 12 games and keeping seven clean sheets in the process.
The 6ft 4in centre half can also play as a holding midfielder, and is understood to have a release clause set at just £10million.
West Brom are weighing up potential targets with Jonny Evans’ future not yet clear. Manchester City and Arsenal are just two clubs to have registered an interest in the Northern Ireland international.
West Brom’s Chinese owners are expected to be travelling ot the Midlands this weekend to watch the Baggies match against Brighton, where they will also discuss their transfer budget for Alan Pardew to utilise this window.