The network has picked up two additional episodes of "Grey's," "Modern Family" and "The Middle," while adding one more to the run of "Castle."

ABC is adding to the seasons of four returning series.

The network on Friday picked up two additional episodes of Grey's Anatomy, Modern Family and The Middle, while adding an extra installment of Castle, The Hollywood Reporter has confirmed.

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The news comes as the network opted to pass on the back-nine order for Shonda Rhimes' Grey's Anatomy spinoff Private Practice, bringing an end to the Kate Walsh medical drama after its current sixth season.

With the orders, Grey's Anatomy, Modern Family and The Middle's respective seasons will run for 24 episodes, while Castle tallies 23.

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Also on Friday, the network picked up two additional scripts for both freshman dramas 666 Park Avenue and Shawn Ryan's critical darling Last Resort, which thus far this fall have been ratings underperformers on their respective Sunday and Thursday slots.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit