The Republic of Ireland international missed the start of the season with a knee injury, and suffered cruciate ligament damage with his country just weeks after making a return.
But Martinez insists the midfielder still has a huge role to play at Goodison Park, and that he has been missed during the 2013-14 campaign.
"Darron has been a big miss for us," Martinez is quoted as saying by the Liverpool Echo. "He has not been forgotten internally.
"I know when you don’t play as a player you get a little bit out of the limelight but I'm very excited about Darron’s contribution next season. He's exactly the type of midfielder we need. Gareth Barry and James McCarthy have been fantastic, but we could have done with Darron being fit and ready.
"He is looking sharp. He wanted to be involved in the final game of the season, but we would have been taking a little bit of a risk to do that.
"But I'm pleased to say he will start pre-season in great condition and ready to fight."
