The Norwegian boss believes he can go right to the top.
The teenage sensation, who has established himself as the Hoops' first-choice left-back this season, put in a Man of the Match performance as the Glasgow giants demolished Greenock Morton 3-0 to move into the Scottish Cup semi-finals.
Leigh Griffiths, Gary Mackay-Steven and Callum McGregor did the damage in a first-half rout, but Deila reserved special praise for Tierney - who set up Mackay-Steven's goal - and says that the youngster has bags of potential.
RD on @kierantierney1 : "He has played consistently for a long time and has done well. He can be a top player."— Celtic Football Club (@celticfc) March 6, 2016
Tierney has won plenty of admirers after displacing Emilio Izaguirre in the side and he is being tipped for a Scotland call-up this month already, despite having only 24 senior games under his belt.
Should he win a promotion into Gordan Strachan's side, it would mean that he bypassed Scotland's Under-21 level altogether, having only represented his country at Under-19 level.
The Bhoys will be joined in the semi-final draw by Rangers, Dundee United and Hibernian or Inverness, although there will be no prizes for guessing who Celtic fans want to be paired with.