One point separates Everton in fifth place and Spurs in sixth, as both sides look to keep themselves in the hunt for a lucrative spot in next season's Champions League.
Deulofeu, on loan from Barcelona, injured his hamstring against Fulham in mid-December, having just started to show the form that had him touted as one of the brightest young talents in Europe.
The 19-year-old attacker has been recuperating in his homeland, but returned to England recently and has been included in the squad for the visit to White Hart Lane.
"Lacina is progressing really well," he told a news conference on Friday.
"I just need to assess if it's wise or not to give him playing time. He is fully fit from a medical point of view, it's just a matter of giving him the right playing time over the next two or three weeks because the last thing we want is him to push himself and suffer as a result of trying to get the tempo and physicality of the Premier League."
Everton have suffered a high injury toll of late, with top-scorer Romelu Lukaku the latest to fall victim with an ankle injury that will keep him for the next few weeks.
Victory on Sunday is crucial for both Everton and Tottenham as they look to keep pace with Liverpool, fourth on 47 points, who meet leaders Arsenal on Saturday.
After a bright start under new manager Tim Sherwood, Spurs have failed to win their last two matches - a 5-1 thrashing to Manchester City and a 1-1 draw with Hull - but Martinez said it was important to prevent them settling into an attacking rhythm.
"They're a dangerous team because under Tim Sherwood this has been developing and we haven't seen the best image yet and that's something we hope we can stop," the Spaniard said.
"It's a learning curve for anyone. When you arrive into a dressing room you need to get to know the players, the partnerships and the way of playing. You look at the results they've had and it shows you this team is getting better and stronger and they haven't peaked.
"People forget how strong their squad is and you know that if this team clicks it will be as good as it gets in this league. We can't let them enjoy their football."