Ernesto Valverde
In July 2011, Greek side Olympiacos earned Grbić's signature in a €1 million transfer from Mogren. During the team's summer camp that year, coach Ernesto Valverde only employed Grbić as a substitute, preferring the likes of Kevin Mirallas. He spent the rest of his time at Olympiacos on loan, first to Levadiakos, followed by Hapoel Be'er Sheva, OFK Beograd, and finally to Partizan.