Ibarbo made his Sagan Tosu debut, where he started the match before coming off in the 56th minute, in a 1–0 loss against Cerezo Osaka in the opening game of the season. It wasn't until on 31 May 2017 when he scored his first goal for the club, in a 3–2 win over Ventforet Kofu. By the time he was deregistered from the team in late–June, he made 14 appearances and scoring once so far whilst on loan at Sagan Tosu. Ibarbo's permanent transfer to the J-League club was confirmed officially by Cagliari and Sagan Tosu in July 2017. A month later, on 19 August 2017, Ibarbo scored his first brace of his Sagan Tosu career, in a 3–0 win over Omiya Ardija. Ibarbo later scored three more goals later in the season. Despite suffering an injury during the 2017 season, Ibarbo went on to make 29 appearances and scoring 6 times in all competitions. Despite this, Ibarbo was one of the key players in the league.
