Nestor of Thessaloniki
Nestor of Thessalonica was a saint and wrestler known for having been the companion of St. Demetrius of Thessalonica (October 26). St. Nestor's feast day is celebrated on October 27. Biography 
Having been moved to act against the mighty Lyaeus, the most feared gladiator in Rome, who mocked and tormented the Christians in the arena, Nestor went to see the imprisoned St. Demetrius and asked for his blessing to fight and defeat Lyeios. With the blessing of the saint and faith in God, he entered the arena and mortally struck Lyeios. Maximian, the emperor, was angered by this and ordered that Nestor be slain with his own sword. Feast day 
The year of his death is reported variously as 290, 296, or 306 AD, each on October 27. External links
 The Passion (BHL 2122) and Miracles (BHL 2123) of St. Demetrius by Anastasius the Librarian tr. by David Woods
Martyr Nestor of Thessalonica (OCA)
Nestor the Martyr of Thessaloniki (GOARCH)
Demetrios the Myrrhbearer & Great Martyr of Thessaloniki (GOARCH)

3rd-century deaths
Saints of Roman Thessalonica
3rd-century Christian martyrs
Year of birth unknown
Military saints