This weekend's news about the recasting of Merrin Dungey (below, left) in one of the lead roles in Private Practice, raises an interesting question of how producers plan to handle the launch of the series this fall since the pilot was actually part of a two-hour episode of Grey's Anatomy.

It might've made sense, Variety notes, to repeat that episode, or even air a cut down version of it, in the first of Private Practice this fall.

But now that Audra McDonald (pictured, right) is taking over the role of Naomi Bennett, the college pal of Kate Walsh's Addison Montgomery, that is unlikely.

There'll be no re-shooting of anything done this spring, Variety reports.

Private Practice will start with a fresh episode that finds Addison Montgomery in L.A. and into her new life at the Santa Monica wellness center inhabited by her new host of quirky co-workers. Any needed back story can be filled in with dialogue in the opening moments.

So why the Merrin Dungey-Audra McDonald swap?

It has been speculated that the chemistry between Dungey and Kate Walsh was not up to par, but Variety reports that it was also a chemistry matter - between Dungey and Taye Diggs, who plays Naomi's estranged husband Sam.

Some were having trouble buying them as a couple.

Audra McDonald, a four-time Tony winner and a Juilliard-trained singer, is known for exuding a natural strength common to great stage actresses.

But the decision to make the switch couldn't have been easy for Shonda Rhimes, creator-exec producer of Grey's Anatomy and its spinoff.

Merrin Dungey is the sister of Channing Dungey, an ABC Studios executive who oversees Grey's Anatomy for the studio and is close to Rhimes.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.