Queensland-raised forwards Hugh McMeniman, Angus Cotterell and Richard Brown all played key roles against a tiring Reds pack.
"We're bitterly disappointed with the performance," said Genia.
"Too many errors, too many times running into touch and too many poor passes ... it wasn't acceptable."
Genia's halves partner Quade Cooper was guilty of many of the wayward passes and was fortunate not to have given up a chargedown try to Chris Alcock in the first half.
It was the blistering pace of Chris Feauai-Sautia who saved the day.
Despite that, the Force still took a surprise 13-12 halftime lead but would have been further ahead if not for the goalkicking of Cooper, who slotted four penalties, and turnovers forced by flanker Liam Gill.
Queensland too often kicked away possession when they had overlaps in their own half and let the visitors make the play.
The visitors took a 13-9 lead in the 32nd minute when Mathewson broke from the fringes of the lineout, brushing off Saia Faingaa on the way, before putting winger Alfi Mafi over in the left corner.
Genia looked sharp for Queensland in his 40-minute comeback from a knee reconstruction and almost ran down Mafi to stop the try.
While the Reds were held tryless for only the third time at Suncorp Stadium, Mathewson almost set up a second try to Junior Rasolea but his long-range break and chip was snuffed by a tiny fumble before the reserve back dived over.
Queensland were forced into a late change when Anthony Faingaa succumbed to a back injury and Mike Harris was the surprise starter at outside centre.