Seth Rogen was cast.
Seth Rogen . Rogen later got a part on sitcom Undeclared , which also hired him as a staff writer . Rogen was cast in a major supporting role and credited as a co-producer in Apatow 's directorial debut , The 40-Year-Old Virgin . After Rogen received critical praise for his performance , Universal Pictures agreed to cast him as the lead in Apatow 's films Knocked Up and Funny People . Rogen co-starred as Steve Wozniak in Universal 's Steve Jobs biopic in 2015 .