Jenson Button described his Belgian Grand Prix as "embarrassing" after energy recovery problems meant he spent the race just "driving around".
Button had energy deployment issues very early in the race and was unable to fight with anyone, finishing over 40 seconds behind McLaren teammate Fernando Alonso in 14th position.
The British driver admitted he had not enjoyed the race at all.
"We had deployment issues," said Button. "It wasn't deploying as it should and it wasn't recovering as it should.
"Basically I was doing the whole straight with no deployment, so after Eau Rouge it would cut, so the whole straight was just for the petrol engine.
"It made it a little bit tougher. Pretty embarrassing, to be fair, just driving around.
"In the last eight laps the guys in front of me made it interesting as they were lapping me, so I had a grandstand view of their race, which was fun to me."
Button conceded even without the problems he would not have been able to compete.
"I haven't had this issue before," he added. "The pace isn't good anyway, as you saw with Fernando, but when you haven't really got any deployment on the straight...
"I was just basically driving around, keeping on the black stuff.
"Fernando was 36 seconds behind the next car and everything was running smoothly. That shows where we are right now. Monza will be the same."