A total episode count for the sophomore season of the 'Grey's Anatomy' spinoff, however, remains unclear.

ABC is keeping Station 19 around for a full season.

The sophomore drama, a spinoff of Grey's Anatomy, has been picked up for a full season. The series, starring Jaina Lee Ortiz, was picked up for a 13-episode sophomore run and on Friday received an order for additional episodes. ABC, however, has not yet firmed up how many episodes that pickup is for.

The Seattle-set firefighter drama, which bowed its freshman run midseason, returned this fall to a wave of series highs. Through its first two episodes of season two, Station 19 is averaging 7.9 million total viewers and a 1.8 in the all-important adults 18-49 demographic with three days of DVR.

Following Scandal's conclusion last season, Station 19 has become increasingly important for ABC. The series is the natural heir apparent to follow Grey's Anatomy on Thursdays at 9 p.m., as the Disney-owned network looks to keep its Shonda Rhimes-produced "TGIT" lineup going after seeing the mega-producer depart for a massive $300 million Netflix deal. With the additional order, ABC will now have both Grey's and Station 19 going all season long, with short-order Rhimes-produced drama How to Get Away With Murder wrapping its run midseason.

Ortiz leads a cast that also includes Jason George, new series regular Boris Kodjoe, Grey Damon, Barrett Doss, Alberto Frezza, Jay Hayden, Okieriete Onaodowan, Danielle Savre and Miguel Sandoval. The series, produced by ABC Studios, counts Stacy McKee as showrunner. Rhimes and Shondaland partner Betsy Beers exec produce alongside producing director Paris Barclay.

Station 19 becomes the second sophomore drama to score a full-season pickup, joining Fox medical drama The Resident.