Peter McCann is facing a fitness battle to make the first leg

The winger, who moved to the Oval from Portadown last month, is struggling with a thigh injury.

Midfielder Gavin Melaugh remains a serious doubt for the meeting with the Shels because of a knee injury.

However, defender Chris Walker will be available for the game after overcoming an Achilles problem.

Former Blackburn player McCann joined the Glens on a three-year contract.

The 24-year-old spent four years at Shamrock Park, picking up a league championship medal in 2002.

McCann was named Football Writers' Young Player of the Year for 2001/02 and is a former Northern Ireland U21 international.

There will be live commentary of both Champions League ties between Glentoran and Shelbourne on Radio Ulster M/W.

Michael McNamee introduces coverage of Wednesday's game from 6.55pm with commentary from Joel Taggart and Roy Walker.