Fermanagh-born Michael McGovern will be on the Celtic bench for Thursday's Uefa Cup fourth-round, second-leg tie against Barcelona at the Nou Camp.
Celtic have given up on Douglas playing in the Nou Camp
The 19-year-old goalkeeper got the call from Celtic boss Martin O'Neill after Rab Douglas's appeal against a ban was turned down.
The tall, muscular McGovern played for Enniskillen Town Colts before heading over to Parkhead four seasons ago.
''They were sounding me out at the weekend,'' said McGovern.
''I was told to pack my bags on Monday. The Nou Camp is not a bad way to start my involvement with the senior squad.''
McGovern played GAA while a student at St Michael's in Enniskillen.
Celtic decided against a second appeal against goalkeeper Douglas's ban after the original appeal was turned down by Uefa on Monday.
O'Neill gave another 19-year-old David Marshall a couple of first-team starts recently and he will face the might of Barcelona at the Nou Camp.