Abstract: The method and apparatus for repressurizing tennis balls or other balls not being normally provided with an air fill valve and for internally sealing the same after repressurizing, which includes: a needle-like element for penetrating the skin of the ball and having a passage therethrough for the passing of a sealing medium and air into the ball, compressing the ball to create a negative pressure therein, a sealant containing member which is penetrable by the extending end of the needle element for drawing the sealant into the ball when the compressive force is released and a source of positive pressure which is attachable to the extending end of the needle element for pressure application to the interior of the ball. The sealant is in flowable condition for a period and and will flow about the internal end of the needle to form a supply about the aperture formed by the needle such that when the same is withdrawn, the sealant will flow in and over the aperture to seal the same.