Legia have confirmed they have submitted an appeal to the Court of Arbitration for Sport over their Champions League expulsion
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Celtic will compete in the Champions League play-offs after the Court of Arbitration for Sport rejected Legia Warsaw's bid to be provisionally reinstated.
Legia took their case to the Swiss-based court after their punishment for fielding an ineligible player was rejected by UEFA's appeal body on Thursday.
But CAS confirmed on Monday afternoon that it had denied Legia's initial request and that Celtic will play Maribor in Slovenia on Wednesday night.
Celtic ran riot on their Scottish Premiership flag day with a 6-1 thrashing of hapless Dundee United at Parkhead.
Jason Denayer, the 19-year-old Belgian defender who arrived on a year-long loan from Manchester City last week, took only four minutes to make his mark by lashing the ball in from close range before goals by Kris Commons and Stefan Johansen had the points tied up by the interval.
In manager Ronny Deila's first game at Celtic Park since taking over from Neil Lennon, stand-in skipper Charlie Mulgrew claimed a fourth and Jo Inge Berget notched a fifth- his first since arriving on loan from Cardiff City - before Dundee United captain John Rankin pulled a goal back with Berget able to make it six in the last seconds.
Celtic have retained their place in the Champions League after Legia Warsaw confirmed their appeal against UEFA's decision to exclude them from the competition for fielding an ineligible player had been rejected.