Borussia Dortmund have opened talks to sign Chelsea defender Renato Veiga on an initial loan deal.
The Blues would prefer a permanent sale should the Portugal international, 21, leave but an obligation to buy at the end of the season could satisfy their demands.
Chelsea have not encouraged the approach from the German club and have already turned down a loan approach from Wolves this month.
Veiga has a substantial role in Enzo Maresca's squad, starting the majority of matches in cup competitions - including Saturday's 5-0 win over Morecambe in the FA Cup third round.