Alonso (right) and team mate Hamilton celebrate on the podium after finishing second and third respestively.
"I was ecstatic. I still am," said Hamilton, Formula One's first black driver.
"I think this is probably beyond my dreams. Obviously to be in Formula One was a dream, but to go into your first race and have such a smooth start is something you don't expect but something we've been working towards," he added.
Alonso, champion for the past two seasons with Renault, said he was happy with his McLaren debut.
"Obviously it's always better to win but today it was not possible," he said. "I think we can be pleased as well. The Ferrari was a little bit too quick for us this weekend."
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