Baines suffered a fractured toe during the Merseyside derby on Saturday and could spend six weeks on the sidelines.
The 28-year-old's injury will force Martinez to shuffle his defensive line-up, but the Everton manager believes there are players who can take advantage of the opportunity.
"When something like this happens it’s an opportunity for other players and can give them excitement," said the Spaniard.
"Obviously you never want to lose players to injury, but unfortunately it's a contact game and that will happen.
"We've had players who have worked hard for five months and deserved an opportunity in the team so they will get that.
"I'm really excited to see how we react as a team and a squad to the demands ahead. It's there for us to try and fulfil our potential.
"I'm looking at the level now of the players who have been very unfortunate not to be in the starting line-up so far, to see how they can show me what they can do."
Martinez opted to utilise Gareth Barry at left-back following Baines' substitution at the weekend, but he also has Bryan Oviedo, Tony Hibbert and John Stones pushing for a first-team place.
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