The 28-year-old Belgium international’s future has been a constant source of speculation in recent months, with his current deal at Stamford Bridge set to expire at the end of next season.
Hazard has long been linked with a move to Real Madrid and that speculation is only likely to increase this summer following the re-appointment of Zinedine Zidane at The Bernabeu.
Chelsea FC are facing a serious battle to break back into the top four this season, with the Blues currently in sixth place in the table and three points behind fourth-placed Arsenal.
The Blues lost ground in the race for Champions League qualification when they suffered a 2-0 loss to Everton at Goodison Park on Sunday.
And former Liverpool FC star Redknapp has warned the Blues that they face a serious problem when it comes to Hazard’s future this summer.
Speaking to Sky Sports after Sunday’s loss, Redknapp said: “Hazard is the key. The reason why he went to Chelsea in the first place was because of the Champions League.
“If they don’t get in the Champions League this year, it gives him an excuse to leave.
“He seems incredibly loyal, he obviously loves the club, he’s been there an enormous amount of time.
“They’ve got a real predicament in the summer because it’s an opportunity to cash in, they can’t buy anyone to replace him.”
Chelsea FC will return to Premier League action after the international break when they travel to Cardiff City on Sunday 31 March.
The Blues finished fifth and won the FA Cup under Antonio Conte last term.
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