West Bromwich Albion have been linked with Celtic playmaker Stuart Armstrong.
Ibrox outfit Glasgow Rangers are third behind Celtic and Aberdeen in the Scottish Premiership.
Celtic assistant boss Chris Davies has spoken of his admiration for winger Patrick Roberts.
Celtic's rampaging left-back has reportedly attracted attention from some of the Premier League's biggest clubs.
The Hoops have conceded seven goals in five games in the league so far.
The 33-year-old has not featured in any of the Scottish Premiership side's last four games.
Scott Sinclair joined Celtic from Aston Villa in the summer transfer window.
The 22-year-old came close to leaving the Scottish Premiership side during the summer window.
The Scottish champions head to the Nou Camp on Tuesday.
The assistant manager is insistent there will be no complacency against Hapoel Be'er Sheva.