Entourage star Connolly will join James Van Der Beek in the CBS sitcom pilot, according to numerous sources.
Connolly's character Bobby Lutz is a gynaecologist with a wife and three children. Described as a "girl's guy" - and something of a nerd in his earlier years - Bobby envies best friend Will (Van Der Beek)'s bachelor lifestyle and womanising ways.
Battleship star Brooklyn Decker was recently cast as successful model Jules, who was discovered by talent scouts in a shopping mall at the age of 13.
Friends With Better Lives' pilot episode will be directed by James Burrows (Mike & Molly, Will & Grace) for 20th Century Fox TV and Kaplan Entertainment.
Dana Klein (Friends, Kath & Kim) and Aaron Kaplan are executive producers.
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