Tennis star Andrey Rublev melted down during his Wimbledon match on Tuesday ... beating himself repeatedly with his racket -- and the wild outburst was all captured on video.
Rublev's temper tantrum happened in the middle of his face-off with Francisco Comesana ... after he failed to return one of his opponent's shots.
As the ball went sailing toward the crowd, Rublev saw red ... and slammed his racket into his knee over and over and over again.
In total, the 26-year-old hit himself seven times .