Hazard left Stamford Bridge this summer for Real Madrid after a season that saw him scorew 21 goals across all competitions and set up a further 17.
With the club under a transfer embargo, the burden to replace those goals has been placed on the shoulders of Frank Lampard's young squad, but Willian believes there are plenty of players capable of carrying it - including Abraham.
"I think Hazard's exit was a big loss," the Brazilian told Goal.
"Eden is a player that can make the difference, but I think we have players that can continue to make the difference as well.
"Abraham is playing well at the moment. He is scoring lots of goals and I am very happy for him.
"The young players are doing well. They can improve a lot. I think Chelsea is Chelsea. No matter the players we have, we have to fight until the end in every competition. That's what we want to do this season."