Sosibios supposedly won the men's wrestling in Athens' Panathenaia while still an ageneios, cf. Call. fr. 384 ll. 37ff.
Described in Callimachus' 384 fragment, Sosibios won many victories, among which one (or more) at the Isthmian games; for the date range, cf. Farrington (2012), p. 128-9 note 330; Farrington there also mentions the suggestion by the scholiast that Sosibios won a victory/victories at the Nemea after his victory/victories at the Isthmia based on his reading of lines 21-5 of the fragment. - PK