'Glee's season five premiere will be delayed due to Cory Monteith's death.

The musical comedy show was due to return on September 19 but after 31-year-old Cory - who played Finn Hudson - was found dead in a hotel room following an overdose of heroin and alcohol last weekend, it has been pushed back until September 26.

Fox said in a statement: ''In light of the tragic passing of beloved GLEE cast member Cory Monteith, the series' executive producers, 20th Century Fox Television and Fox Broadcasting Company have jointly decided to delay the start of production of GLEE until early August. Season Five of GLEE will now premiere on Thursday, Sept. 26 (9:00-10:00 PM ET/PT) on FOX. No further details are available at this time (sic).

While Cory - who first entered rehab at the age of 19 - spent time in a treatment facility in March after relapsing, those close to him insist he never let his addictions affect his work on 'Glee'.

The insider explained: ''I never saw him come to work late, lose his temper, not know his line or argue with his castmates.

''The cast members make a one hour musical every nine days. You'd have to be superhuman to use drugs with any regularity and get the work done.''