Bellamy, 33, linked up cleverly with his 35-year-old strike partner to restore City's lead in the 54th minute after Josh King briefly brought Rovers level following Mark Hudson's opener. Helguson also laid on goals for substitutes Lee Mason and Kim Bo-Kyung as the Bluebirds made it five wins in six unbeaten games.
"Craig and Heidar will have a day during the week where they'll go to the pool and do some stretching and not go out on the grass, but come 7.45pm on a midweek and 3pm on a Saturday they show that experience," said Mackay.
"Craig's been out for four weeks this season with a swollen ankle and a couple of weeks with a knock on his knee but I want bravery - I want people in those positions and a desire to do that. He does it every day in training. He wants to train every day and I have to pull him back and say 'no, you're going to the pool today'.
"In games you've got to just let them go and sometimes they take the knock and get up.
"The work that him and Heidar did for the second goal was incredible - he flicks it on to Heidar, Heidar flicks it back to him and he puts a magnificent finish in. They've both got their heart on their sleeves and that's what I like."
Having presided over a third defeat in four winless matches before Blackburn's lowest home crowd of the season, home boss Henning Berg admitted the better side took the points - albeit with a touch of late gloss applied to the scoreline.
"We are disappointed to lose another game at home," said Berg, who insisted Rovers' target for the season remained promotion even though results on Saturday could leave them seven points from the play-off places.
"We think Cardiff were the better team all over, although maybe not as much as the scoreline suggested but you can't have any complaints.
"They were more experienced than us, they had far better finishing and they also defended better than us - I think that was the key in this game."
- Sports & Recreation