エルネスト・バルベルデ
On 24 June 2011, Olympiacos agreed to sign Katai on a four-year contract. At his first trainings with the club, coach Ernesto Valverde told Katai that he did not defend enough and that he needed to improve as a player. Katai did not play a single match for Olympiacos, but was instead sent on loan four times.