Formula One champions Renault expect still to be trailing rivals Ferrari and McLaren at Sunday's Spanish Grand Prix.
Pat Symonds (left) has praised Fisichella's performances this season
Despite making progress in improving their car after a disappointing start to the season, head of engineering Pat Symonds does not expect quick progress.
He said: "The road back to our normal level of competitiveness will be a long one, we are not expecting leaps forward in competitiveness this weekend."
The champions are fourth overall with just nine points from three races.
Renault won at the Circuit de Catalunya last year with Fernando Alonso but the Spaniard, now a double world champion, joined McLaren at the end of 2006.
Giancarlo Fisichella, now partnering Finnish rookie Heikki Kovalainen, has scored eight of their nine points, and has already written off their title chances.
But Symonds praised the Italian's contribution this season.
"Giancarlo has been very impressive so far this season," he added.
"A lot of our esteem for him is rooted in the way he handled our 2001 season, when he put huge effort into making the most of a difficult car.
"We are seeing something similar this year. The R27 is a hard car to drive consistently, but in spite of this, he has driven very consistent races.
"He has taken the car to the limit of what it is currently capable of, and contributed in every way he can to helping resolve our current problems. We couldn't ask any more of him."
Meanwhile, fifth-placed Toyota are hoping to show that they have narrowed the gap with the top teams.
They are four points behind Renault, and driver Ralf Schumacher believes they will be more effective this weekend.
He said: "We have made some aerodynamic changes to our car since the last race. My goal is to get back among the points after two disappointing races."