The G1 (Grade One) Climax professional wrestling tournament is a weeklong event held each August by the New Japan Pro Wrestling promotion. The G1 draws standing room only crowds each night, record receipt gates and generates front-page coverage on the sports sections of several of the daily newspapers in Tokyo. Though it has sometimes been held as a single-elimination tournament, it is usually (and currently) held as a round-robin, with winners from two blocks wrestling in the final to decide that year's winner. The winner of each block is determined by a points system; two points for a victory, one point for a draw, and zero points for a loss.

G1 Climax 23: Day 1 (2013) is currently not available on any services.