Sean Saintmichael Plott[2] (born June 27, 1986), better known as Day[9], is an American esports commentator, player, event host, streamer and game designer.

Plott is best known for his contributions in the professional StarCraft scene, where he regularly appeared first as a player and later as a commentator and host at various tournaments for the game for many years.

After college, Plott attended the University of Southern California in Los Angeles earning a Master of Fine Arts in interactive media in May 2011.

In each episode, guests such as Felicia Day and Grant Imahara take on Plott with the hope of emerging victorious in an all-or-nothing match, while teaching the audience the tips and tricks to become better at the game.

[17] At the company, Plott worked on the real-time strategy game Guardians of Atlas, which opened to beta testing 2016.

[21][22] In 2020, Plott worked alongside ControlZee Inc. to make a "massively interactive swarm game" called Straits of Danger on the dot big bang platform.