For once, NBC is deciding to keep things simple.

Rather than shuffling its fall schedule to make room for freshman shows "Parenthood" and "Mercy" swapping their fall and midseason launches, it's merely substituting one for the other.

"Parenthood" was originally scheduled to premiere at 8 p.m. ET on Wednesday, Sept. 23. Last week it was announced that the show would be pushed to midseason to accommodate cast member Maura Tierney having a tumor removed from her breast and an eight-week medical evaluation.

In its place, the nursing drama "Mercy" will slide in to the same premiere date and time. The show has already been notified to be ready to go into production earlier than expected.

Find out about all of NBC's new shows

As Zap2it reported earlier this week, having her new show "Mercy" will not prevent one of its stars, Michelle Trachtenberg, from guest-starring on the new season of "Gossip Girl" since time off for The CW drama was already written into her contract.