kept attacking, but Arona submitted him in the second round with a kneebar. Afterwards, Arona took part in a tournament for the RINGS Middleweight Championship, facing Jeremy Horn again in the first round and beating him by unanimous decision. The final match was against Gustavo Machado, who Arona defeated with kicks and punches in 1:29 to win the tournament and the title. PRIDE Fighting Championships After being noticed in RINGS, Arona was offered a contract to join PRIDE Fighting Championships. He started his career there strong, defeating Pancrase veteran Guy Mezger, but his victory would be a controversial one. Mezger managed to stop Arona's takedowns and landed strikes, including a glancing head kick and several punches through the guard, which forced Arona to defend; it took two rounds for the Brazilian to come back, taking down Mezger and executing ground and pound until the end of the third round. Arona won a split decision, which was disputed by some sources, including the announcers of the match. Ricardo's next fight would be against another high ranked opponent, Dan Henderson. This time Arona was able to take down the wrestling champion, but Henderson executed his own takedown and landed knees and punches to the face until Arona could escape. The Brazilian switched his strategy and knocked down Henderson with a right hand, though the American still reversed and ended the first round attacking Arona's guard. At the second round, despite receiving a cut over his eye, Arona managed to overpower Henderson and punish him from the top. He looked to have secured a rear-naked choke, only for Henderson to escape, but Arona controlled him to end the match and got the split decision. At PRIDE 23, Arona would go against Murilo Rua, a member of the Chute Boxe team, which was in a rivalry with Brazilian Top Team at the time. The two contenders fought a series of battles on the clinch, in which Arona imposed his superior wrestling, and almost finished the fight with a rear-naked choke and an Achilles lock at the end of the first round. The match went back and forth, with Murilo escaping from sparse submissions and landing his famed strikes, but Arona overpowered him with takedowns and kicks at the end and won the unanimous decision. The victory over Rua was followed by Arona's first defeat in PRIDE, losing his fourth fight to Quinton Jackson in