CHELSEA will let keeper Thibaut Courtois leave for FREE instead of selling him this summer. The Belgium stopper is in a stalemate over extending his contract beyond the end of next season, when he can leave without a transfer fee. And the Premier League champions are willing to let him run down his contract rather than cash in early. Real Madrid are interested in the 25-year-old as a long-term successor to Keylor Navas at the Bernabeu. Courtois played for rivals Atletico Madrid on loan for three seasons and returning to the Spanish capital as No 1 for Real is considered a dream move for keepers.