After Joe Mason had put the Bluebirds in front, Hudson unleashed a shot from inside his own half that caught Derby keeper Frank Fielding back-peddling before dipping into the net to seal Cardiff's 2-0 victory on Tuesday.
Mackay has no doubts that his captain meant to score the 60-yard effort that was reminiscent of David Beckham's goal for Manchester United against Wimbledon in 1996.
"It was a real good piece of skill. Mark stepped out from the back ahead of the attacker, looked up and absolutely meant it. He executed it," said Mackay.
"Mark is an accomplished footballer and he saw him off the line. I'm delighted for him and the goal capped off an exceptional performance. I don't care if it was better than Beckham's. It was our second goal and meant we got three points.
"We know three more points will seal our play-off place. We have a tough game against Leeds United on Saturday and we will concentrate on that, rather than look at other results."
Cardiff are now looking on course for a spot in the play-offs as they sit four points clear of nearest rivals Middlesbrough in sixth.