Powell has long been linked with Celtic, and is out of contract at Wigan.
Celtic's Tom Rogic played for Australia on Saturday.
Tom Rogic is set to feature tonight for Brendan Rodgers' Celtic side in the Europa League.
Celtic midfielder Tom Rogic is in terrific form.
Brendan Rodgers’s Celtic won against Heart of Midlothian on Saturday.
Tom Rogic opened the scoring as Celtic thrashed the Scottish Premiership's bottom club Dundee on Wednesday at Dens Park.
Ajer and Rogic both reached Celtic milestones on Wednesday night.
Rogic is beginning to rediscover his form for Celtic.
Brendan Rodgers’s Celtic will face Heart of Midlothian in the Scottish League Cup on Sunday.
Celtic's Scottish Premiership champion Tom Rogic is expected to be a key player for Graham Arnold in the Australia national team.
Southampton are reportedly keen on signing the Celtic ace, but West Ham United could steal march on their Premier League rivals.
Celtic have done some excellent pieces of business since the inception of the January transfer window.
Celtic swept aside a poor Motherwell side in the Last 16 of the Betfred Cup, winning 5-0.