The defending Premier League champions have been disappointing in their second season under Italian head coach Antonio Conte.
Chelsea FC are in fifth place in the Premier League table and a staggering 10 points adrift of Liverpool FC and Tottenham Hotspur in the race to secure a Champions League spot.
The west London side crashed out of the Champions League last month following a 4-1 aggregate loss to La Liga outfit FC Barcelona in the round of 16.
The Blues forward has scored 11 times and has made three assists in 28 games in the Premier League in the 2017-18 season so far.
Hazard hasn’t signed a new contract with the defending champions and has been linked with a potential move to Real Madrid in the summer.
Former Liverpool FC star Redknapp believes Chelsea FC will struggle next season if Hazard does call time on his career at Stamford Bridge.
“Chelsea must be concerned that Eden Hazard has not signed a contract extension, despite them apparently being prepared to pay him £300,000 per week,” Redknapp told the Daily Mail.
“Take Hazard out of that team and there is no way they would be able to match Manchester City, Manchester United or even Tottenham next season. Chelsea have to play this one carefully.”
Chelsea FC won the Premier League title with two games to spare last term after the Blues finished seven points ahead of Tottenham.
The Blues signed Ross Barkley, Emerson Palmieri and Olivier Giroud in the January transfer window.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news