Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
second-best [sɛkəndˈbɛst] n не са́мое лу́чшее nt adj
adj (hotel, room) второ́й по каче́ству; (pupil) второ́й (по успева́емости)
as a second-best за неиме́нием лу́чшего
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.