Celtic were beaten 1-0 by the Lincoln Red Imps in the Champions League on Tuesday.
Celtic were beaten by the Gibraltar based minnows in the Champions League on Tuesday.
The former Premier League boss is preparing for his first season with the Hoops.
The striker inspired the Hoops to the Scottish Premiership title.
Former Celtic striker Frank McGarvey has urged Ronny Deila to work hard to keep his squad together over the summer.