Sunderland simply had no answer to the crisp passing and off the ball movement of their opponents and disgruntled home supporters were streaming out of the ground long before the final whistle.
Manager Peter Reid offered no excuses for a ragged performance which even at this early stage of the season is of major concern following an investment of £22million in the past year.
"We started alright and had a couple of chances, but we didn't take one," said Reid. "They scored, anxiety set in and there was a lack of confidence and that's not taking anything away from Fulham.
"We were all over the place for the goals. We lost our shape, we lost our discipline. We were two different teams before and after they scored, but teams are coming here and we are making it too easy for them."
But Inamoto was again the creator for Marlet to put the issue beyond doubt in the 78th minute with another well-taken goal.
Edwin Van Der Sar made a brilliant save from Quinn but it was too little too late from the veteran striker who is going to be difficult to replace when he hangs his boots up in the not too distant future.