The west London club are reported to be considering the former Hull City manager as they look to reduce expenditure.
With their pursuit of Julián Álvarez stalling, Barcelona are exploring alternatives as a post-Lewandowski rebuild takes shape.
Deco is quietly laying the groundwork for the summer, but decisions on current squad members must come first.
The Catalan club are open to signing the Portugal full-back outright, but only if specific requirements are met this summer.
The veteran Poland goalkeeper has informed the club he intends to honour his current contract, easing one of several summer decisions.