LOS ANGELES (thefutoncritic.com) -- NBC has postponed production on its new drama "Parenthood," citing a medical evaluation that co-star Maura Tierney is undergoing.

The eight-week delay will push the series off the Peacock's fall schedule to a midseason berth. Filming had been set to begin on July 27. "Start of production on NBC Universal's new series 'Parenthood' has been postponed for eight weeks due to medical evaluation that valued cast member Maura Tierney is undergoing," NBC said in a statement released to The Hollywood Reporter. "The top priority for NBC, Universal Media Studios and Imagine Television is the well-being of Ms. Tierney. We are unable to release further details and ask that you respect her privacy at this time."

It's not clear what will take over on Wednesday nights at 8:00/7:00c however speculation suggests the network will simply bump up the start of midseason entry "Mercy," which had been set for the same slot come next year. The Peacock however may be hesitant to launch two new medical shows in the same quarter, having slated fellow newcomer "Trauma" for Monday nights at 9:00/8:00c.

Delays like these aren't unprecedented: The WB infamously tabled its fall drama "Fearless" in favor of launching then midseason entry "One Tree Hill" back in 2003 while ABC opted to stick with expanded episodes of "Dancing With the Stars" rather than roll out "The Knights of Prosperity" in the fall of 2006.