With Ferrari's F2012 having fallen short of the team's high expectations, there has been speculation that both Domenicali and Massa could be fighting for their futures if the situation does not improve.
But Alonso is in no doubt that both men are doing an excellent job - and he sees no reason why any thought should be given to change.
Writing on his official website in response to questions from fans, Alonso said about Massa: "He's one of the best drivers in the world, and he has shown it during his whole career.
"It's easy to praise when you have a good car but also to criticise when you have a bad one. I lived similar situations during my last stint at Renault, when some of my team-mates were unfairly criticized and now, they are being praised once again."
When asked about Domenicali's situation, and whether it would be better to have someone like Flavio Briatore in charge, Alonso said: "Stefano's work is fantastic in every sense and I can't think of anyone better than him.
"As I explained before, it only takes one race to pass from criticism to praise. I'm very good friends with Flavio and we talk frequently. He's one of the most intelligent people I've ever met."
Alonso also revealed that he was troubled by severe leg pain at the start of the 2010 campaign.
"I think the time I suffered most was at the beginning of last season, when I was suffering from an injury to the sciatic nerve which caused me a lot of pain to the leg towards the end of races," he said.