The move was done by a Sharks fan in a spin-off of a Red Wings tradition.
"It was done for fun to mock Detroit throwing their octopus on ice; mission successful," the unnamed man said.
The man with the golden arm did not want to be identified because he does not want to lose his season tickets, but he was willing to share how he gets a 3-foot leopard shark through security and into the tank (HP Pavilion).
"It was carefully strapped to the leg of a teammate; Velcro straps and duct tape are always necessary in an operation like this," he said.
Once inside, his team of six waited for the introductions to remove the shark and place it under their seat.
"Nobody smelled it, it was pretty fresh, only the freshest shark for this occasion," he said.
It was a tough throw from 14 rows up.
"Got to get it over the glass; be careful not to hit the lady in the front row," he said.
The shark toss was clearly aimed at the Detroit tradition of throwing octopi on the ice during the playoffs. It originated in 1952, when there were only two rounds of playoffs, so it took eight wins to bring home the Stanley Cup.
"That silly octopus has been in our way for a bunch of years; it was time for the shark to swallow the octopus and it did last night," the man said.