Another hustler, whose first name is Kenny and whose street name is Little Daddy (he is 5 feet 3 inches tall), said he could always tell how good his opponent was in the first couple of moves. For example, he said, if someone moves quickly but fumbles the pieces, or uses one hand to move the pieces and the other to hit the clock, which is against the normal rules of speed chess, then the person is not experienced.

Little Daddy, who said he started playing street chess in 1976, said he won about 80 percent of the time. A crucial part of the game is not to win too quickly, he said.

“You make the games close,” he said. “You don’t want to crush them. You want to leave their ego intact, because you want to keep them coming back.”

Russian Paul, who displayed the opening knowledge, speed and tactical ability of a master (but not the much higher grandmaster), said he had been playing in the streets for about 15 years and always tried to win. “If they get scared away, it is not my problem,” he said.

Like bartenders, the chess hustlers have names for people who keep coming back and coughing up money: regulars, or customers.

Little Daddy said that every hustler  there are about a dozen in Union Square, although the number fluctuates during the day  had at least a couple of regulars.

On this particular night, Carl Neblett, a regular, was taking on Junior, who always wears a baseball cap and keeps up a running commentary as he chain-smokes his way through games.