The experienced South African has made just one appearance in the calendar year of 2015 to date, with injury problems blighting his last two seasons at Goodison Park.
However, Pienaar played for Everton's under-21 side against Schalke on Tuesday, and he is starting to edge closer to a return to full fitness.
And Martinez said: "Stevie is a unique footballer within our squad and we need to get him fit because the margin we can improve, with him in the squad, is huge.
“So we are really looking forward to him having a good exercise tonight and we will build it up slowly.
“We all sympathise with the tough period he’s had to go through.”
Pienaar is one of the longest-serving members of Everton's squad, with the creative midfielder having spent two lengthy spells at the club.
During that time he has showed his poise in possession on numerous occasions, and his vision will be valuable to the team in an attacking sense.
The Toffees have a number of exciting, young talents, but having Pienaar's steadying influence in the side could help them become an even greater threat.
Pienaar's return to the first-team is not imminent just yet, but the 33-year-old will hope to continue building his fitness levels for the development side, as he aims to stay off the treatment table for a prolonged period of time.