Police are looking for a coach shown on video sucker punching a boxer following a match

One of the cheapest of cheap shots you'll ever see,

There's no excuse for this.

A fight between two boxers was marred after a corner man went into the ring and video shows him punching one of the combatants — and now, reports say police are involved.

Let's set the stage:

Andre Dirrell and Jose Uzcategui were battling for the interim IBF 168-pound title fight Saturday when Uzcategui was disqualified for knocking Dirrell out after the bell in the eighth-round. Here's what happened:

Clearly, that's a DQ. Afterwards, in a display of sportsmanship, both fighters embraced.

But then things went off the rails. A man identified as Leon Lawson entered the ring and a video shows him throwing a punch that lands squarely on Uzcategui's jaw. You can also hear the announcers ' shock:

The reaction was immediate and harsh .......

Afterward, Dirrell apologized:

ESPN then reported that police are looking for Lawson, but don't know where he is.