Ross Brawn says it was no fault of Michael Schumacher's that he didn't finish the Monaco GP after being hit with the fuel pressure problem.
Schumacher claimed pole position for the Monte Carlo street race but dropped to sixth as a result of a penalty he had incurred at the previous in Spain.
A difficult start on Sunday, where he was hit on the opening lap by Romain Grosjean, meant Schumacher was not able to make a quick start and he fell to P8.
The seven-time World Champ worked his way up to seventh before a problem with his car saw his lap times drop by almost five seconds a lap.
Falling out of the points, Schumacher brought his car into the pits and retired.
"He was hit on the run to the opening corner which cost him positions, but was very quick when a fuel pressure problem started to slow him later in the race," said Brawn.
"We tried to continue but it was costing him too much time, dropped him out of the points and forced us to retire the car.
"It was very disappointing because he put in a great performance this weekend and he was still on course to score useful points."
The Mercedes team boss added: "We need to make sure we eliminate the problems for him, starting in Canada."
