Originally published on ProWrestlingSheet.

Pro Wrestling Sheet has learned Matanza Cueto required multiple stitches following his match Saturday night in Boyle Heights ... and it's all because he sliced a vein while punching a window.

Sources in attendance at the Lucha Underground taping tell us Jeff Cobb -- the man behind the Matanza mask -- punched a window during a hardcore match and began to bleed heavily.

The match was cut short after his injury quickly became apparent and Cobb was taken to a nearby hospital for stitches. Rey Mysterio and Dragon Azteca filled the extra time by running to the ring and beating up PJ Black and Johnny Mundo while backstage officials handled the situation.

Sources tell us Matanza can't get back in the ring until the stitches come out and he's been forced to cancel bookings next week. However, we're told he should be good to go by the next LU taping.

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