Joe Mason's fifth goal of the season in the 41st minute earned Cardiff their fifth successive win and their third consecutive away success - form which deservedly keeps them at the top of the table with a seven-point gap to Hull in second.
Mackay, who had to make five changes, said: "It was a tough team we played and we knew we had to battle and fight for everything we got.
"We are now seven points clear at the top but it is just about making sure about the game you are in and keep chalking them off.
"It has been a tough period but we have the momentum and consistency which I am delighted about.
"We were without Andrew Taylor who fell ill on the morning of the game. Simon Lappin came in and did a good job. He showed why he has played at the top level.
"It was a professional performance by the team.
"You've got to be in this division as you have to respect the opposition because you are not going to score bags of goals.
"To come away with the 10th clean sheet for the season was outstanding and we were very comfortable in the second half."