Game is drawn by mutual agreement
In game 4, Deep Blue proved that it was the real thing by drawing with Kasparov. Like game 1, it was an open game, and one in which Kasparov seemed frustrated by his inability to mount an attack against the unassailable tactics of Deep Blue.

Toward the end of the middle game, things started to look a little dicey for the champion. As the 40-move time control approached, the additional pressure of the clock seemed to weigh heavily on Kasparov. However, he reached time control, and formulated a plan which ensured him the draw. Deep Blue's team refused his draw offer once, but finally relinquished hope of a win after Garry initiated a clever rook for knight and pawn sacrifice (link to chess glossary). The material advantage for Deep Blue could not be exploited because of the threat of a back rank mate of the Black King. The game was drawn by mutual agreement on the 50th move.