ISTANBUL, TURKEY - DECEMBER 09: Head coach of Celtic Ronny Deila (R) and Celtic's football player Callum McGregor (L) attend a press conference before the UEFA Europa League Group A football match between Fenerbahce and Celtic at Fenerbahce Sukru Saracoglu Sports Complex in Istanbul, Turkey on December 9, 2015. (Photo by Elif Ozturk/Anadolu Agency/Getty Images)