The so-called Ninth Isthmian is fragmentary. Here’s the whole thing:
Pindar, Isthmian 9
The story of Aiakos is famous–
Aegina, known for her ships, is famous too:
Hyllus and Aigimos brought
A Dorian army to found it.
The citizens live under the rule of law,
Offending neither justice nor custom
For foreigners. When it comes to excellence?
They are like dolphins in the sea:
Wise guardians of the Muses and athletic competitions.”
“Within the Corinthian lands there is the place called the Kromyon after Poseidon’s son Kromos. There is where men claim that sow called Phaia was nourished (she was one of Theseus’ deeds). When I was there, pine forest was growing along the shore where one would find the altar of Melicertes. The story is that a dolphin carried a boy to that place and that after Sisyphus found him lying there, he buried him on the Isthmus and established the Isthmian games in his honor.
This is near the start of the Isthmus where Sinis the brigand used to grab pine trees and pull them to the ground. He took all the men he overcame in battle, bound them to the tree, and let it go again. After that, the pine trees would draw the bound man toward itself, but since the binding did not give way in either direction, the victim was split in two, tearing on both sides. Sinis suffered this same death himself thanks to Theseus.”