Mark McLinden was a key figure for Harlequins
Catalans: (12) 28
Tries: Wilson, Greenshields, Jones (2), Bentley
Goals: Bosc (4)
Harlequins: (18) 32
Millennium Magic began with a bang as Harlequins battled back for a high-scoring win over the Dragons.
Tries: Smith, Sykes, Wells, Randall (2)
Goals: Purdham (6)
Catalans' Clint Greenshields and Stacey Jones cancelled out early Andy Smith and Jon Wells tries but Chad Randall restored Quins lead before half-time.
John Wilson, Jones again and Andrew Bentley put the Dragons ahead after the break but Paul Sykes stemmed the flow.
Randall earned a well-deserved second to nose Quins ahead and Rob Purdham's goal gave them breathing space.
With Catalans v Harlequins being the sole non-local match-up game in Cardiff and the first of six games on the bill, the pressure was on the teams to get things off to an eventful start.
And Quins certainly did their best to fulfil that with two tries in the first 10 minutes.
First Smith went over after Danny Orr's kick-through, and then Mark McLinden's looping pass missed out Tyrone Smith to put Jon Wells over.
The Dragons did not get a sniff in the early stages but just as Harlequins may have thought they were in for an easy day, two tries in as many minutes turned the game on its head.
The first came when Jones set up Greenshields to score, despite the best efforts of Chris Melling to hold him up.
Second later Jones added one of his own, and although Randall restored Quins' lead before the break, the French side had shown they meant business.
That became even more evident as they ran in three tries in a row early in the second half, to take the lead for the first time.
The first came when Jones kicked through and Wilson timed his jump to perfection to touch down, Jones then added one of his own before Bentley finished off a move started by Jerome Guissett to leave Quins reeling.
A clever cross-field move allowed Sykes to score as the Dragons' points blitz came to an end, and Quins took advantage of this lull to battle back into the lead.
A sustained period of pressure climaxed in Randall scoring his second, and having converted all the tries, Rob Purdham then added a goal to give the Dragons a degree of comfort.
Catalans coach Mick Potter on a possible forward pass in the build-up to the decisive try:
"I will be looking at the video very closely.
"I am sure we deserved to get something out of the game. I thought we did well to get into a winning position."
Harlequins coach Brian McDermott on Luke Burgess playing after the death of his father:
"He made a call to play and he won't make too many bigger calls in his career.
"I reckon his dad would be over the moon with him. He handled himself like a really mature bloke.
"The players didn't know and they wouldn't have suspected either. He has done a hell of a job."
Catalans Dragons: Greenshields, Murphy, Wilson, Mogg, Duport,
Bosc, Jones, Casty, Quigley, Chan, A. Bentley, Gossard,
Replacements: McGuire, Ferriol, Guisset, Teixido
Harlequins: Melling, Wells, Sykes, T. Smith, A. Smith, Orr,
McLinden, Temata, Randall, Heckenberg, Purdham, Hopkins, Hill.
Replacements: Rinaldi, Grayshon, Burgess, Walsh.