Craig Sandercock blamed "too many errors" as his Hull KR side were beaten 24-32 by Catalan Dragons at Craven Park.
A poor first half proved costly for the Robins and despite a better performance after the break they were unable to make good.
"Too many errors, forced offloads and penalties cost us," Sandercock said.
"The play count was two to one in their favour.
"They got the advantage and rolled on with it."
One of the few bright spots for Rovers last season was keeping the French side to three tries or less in three close encounters, but Catalan scored four in the first half today after Michael Dobson gave Rovers a third-minute lead with a penalty.
The lead only lasted four minutes as Thomas Bosc sent Zeb Taia over for a try and Bosc converted for a 6-2 lead which Jason Baitieri extended as he took advantage of some slack defending from Rovers.
Super League's oldest player Steve Menzies then rolled back the years with two tries in the closing stages of the first half.
His first came when Brent Webb's pass caught Rovers off guard on their left-hand side. The best try of the half came on the opposite flank when Jamal Fakir broke with electric pace before sending the 39-year-old Menzies away for a simple score. Bosc landed three of the four conversions as the home side struggled.
Rovers' problems worsened three minutes after the break. A breakdown in communication 20 metres from their own line between Con Mika and Lincoln Withers gifted Catalan possession from which Fakir ran through unopposed to score. Bosc missed the conversion but the Dragons led 26-2.
Rovers finally got over the Catalan line in the 51st minute from a superb offload from Cory Paterson.
It was just what Rovers needed with half an hour to play and another Paterson offload helped set up Rovers' second try. A Dobson kick was dropped a metre from his try line by Webb and fell invitingly for Josh Hodgson to pick up and score. Dobson converted to make it 26-12.
Suddenly Rovers were on top and they made the most of their dominance when Omari Caro scored his side's third try of the game. Centre Liam Salter provided the perfect flick pass for the winger to score and Dobson converted to set up a tense finale.
However, Webb then secured victory for the Dragons with the killer try. Young prop Julian Bousquet powered through a gap in defence and offloaded for Webb to score.
The game's final score came for the home side when Hodgson found Withers to open his account for the season with two minutes remaining. Dobson's conversion made the final score 32-24.
Sandercock was pleased with the efforts of his players as they rallied to close to within eight points.
"The second half was something we should have done in the first half," he said.
"The effort from the boys is undisputed. They tried hard but the first half cost us dear with the possession we gave away."
