The 24-year-old defender endured mixed fortunes during his first season at the Santiago Bernabeu, after arriving in Spain from Benfica in a £27million deal in the summer of 2011.
And, after Coentrao reported late for Real Madrid training on New Year's Day, the La Liga champions are now believed to be looking into the possibility of offloading the left-back in the January transfer window.
Chelsea were interested in signing the Portuguese international when he chose to link-up with his compatriot Jose Mourinho in the Spanish capital, and with Ashley Cole heading for the Stamford Bridge exit, the Blues might be interested in revisiting the chance to bring Coentrao to west London.
Interim manager Rafa Benitez does have Ryan Bertrand - seen as Cole's natural successor - in reserve, but Chelsea are determined not to rush the England youngster in his development.
Meanwhile, Manchester City have Gael Clichy and Aleksander Kolarov as their current first-team options at left-back, but news of Coentrao's availability might still tempt Roberto Mancini into renewing interest in a former target.