The Belgium international has made a brilliant start to the Premier League season following five goals in five games despite an exhausting World Cup campaign.
Hazard started the third round tie on the bench but Maurizio Sarri introduced the 27-year-old following Daniel Sturridge’s breakthrough goal in the second half.
Emerson Palmieri levelled the cup clash before Hazard skipped past three Liverpool FC defenders before the Chelsea FC number 10 curled a finish past Simon Mignolet with five minutes to play.
Hazard has now scored six goals in eight appearances in all competitions to find his top form under new Chelsea FC manager Maurizio Sarri.
Former Blues defender Townsend lavished praise on Hazard for his impressive performance.
“If you were a Liverpool supporter or player, you might feel that Chelsea have pinched it,” Townsend told BBC Sport.
“Liverpool were in control for large periods, they certainly started better in the second half and then got in front.
“But when Hazard is on the field anything can happen – it was a magnificent strike.”
Chelsea FC will take on Liverpool FC in their next Premier League game at Stamford Bridge on Saturday evening.
The Blues are two points adrift of the Premier League leaders Liverpool FC after six games.
The west London side finished in fifth spot in the Premier League table last term to miss out on a place in the Champions League.
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