A drop goal from James Maloney in golden point extra-time sealed a 29-28 win for Catalans against Hull KR.
The Dragons took an early 12-0 lead thanks to tries from Fouad Yaha and Matt Whitley before Ryan Hall pulled one back for Rovers.
Catalans debutant Mathieu Laguerre scored late on in the first half to give Steve McNamara’s side an 18-4 lead at the break.
Ben Garcia and Yaha extended Catalans’ advantage to 28-10 shortly after the second half restart.
But Hull KR fought back and young half-back Mikey Lewis got on the scoresheet before Hall got his second of the match.
Catalans forward Julian Bousquet was sin-binned in the 66th minute for running into a melee, and suddenly Hull KR were on the front foot.
Hall completed his hat-trick in the 71st minute, with Ireland international George King storming over for Hull KR five minutes later to draw the score level at 28-28 and send the game into golden point extra-time.
A brilliant break from Arthur Mourgue saw Maloney in good space for the drop goal, with the Australian then slotting the one-pointer through the uprights to seal an opening round win for the Dragons.
Catalans: S Tomkins; Davies, Laguerre, Whare, Yaha; Maloney, Drinkwater; Goudemand, Da Costa, Bousquet, Whitley, McMeeken, Garcia. Subs: Mourgue, Seguier, Baitieri, Kasiano.
Tries: Yaha (2), Whitley, Laguerre, Garcia Goals: Maloney 4 Drop Goals: Maloney 1
Hull KR: Quinlan; Crooks, Minikin, Kenny-Dowall, Hall; Abdull, Lewis; Sims, Litten, King, Linnett, Hadley, Lawler. Subs: Vete, Parcell, Minchella, Storton.
Tries: Hall (3), Lewis Goals: Abdull 3