Udinese's Europa League group has changed with news Sion were thrown out for fielding ineligible players, replaced by Celtic.
The Friulani are in Group I along with Atletico Madrid and Rennes.
Sion had beaten Celtic in the play-offs, but UEFA threw the Swiss side out of the competition for fielding several players in contravention of a worldwide transfer ban.
The Swiss FA had argued the two-year ban, imposed after the illegal 2008 capture of Essam El-Hadary from Al-Ahly, had already expired.
UEFA rejected that appeal today and have reinstated Scottish giants Celtic in Udinese's group.