At this precise moment, there are two kinds of sports fans in the world: those who say Robin Ventura hit a grand slam in the bottom of the 15th inning Sunday night to end the longest game in baseball playoff history, and those who say he merely hit a single.

This is the great divide between rule-benders and rule-enforcers, between sensualists and statisticians, between those who trust their own eyes and those who trust Rules 6.09(d), 10.07(f) and 10.07(g).

Everyone saw the same thing. Ventura, batting for the Mets with the bases loaded and the score tied 3-3, promptly launched the ball over the 371-foot sign on the right-center field fence. Grand slam! On TV the little scoreboard in the corner immediately said "Mets 7, Braves 3." But in the euphoria of winning the game, only one runner crossed home plate, and Ventura was mobbed by his delirious teammates before he reached second base.

The official scorer was a 70-year-old retired New York Daily News sportswriter named Red Foley. (Most great characters in sports are named Red.) Foley is the kind of fellow who says things like "Well, I'll be a monkey's uncle" and "Oh, for crying out loud." He saw that Ventura didn't reach second base. Amid the pandemonium--fans screaming, music blaring--Foley, standing in the press box, knew how he had to score it.

"It sounded like World War III. A bunch of people come running to me," he said yesterday. "I said it can only be a single."

Foley marked the game as a 4-3 Mets victory, with three Mets left on base. He knew that an obscure rule, put in place after the Yankees' Chris Chambliss was swarmed by fans after hitting a game-winning home run in 1976, would have given Ventura the home run had it been fans who had prevented the run around the bases.

But in this case, Ventura's own teammates were the obstacle.

He also knew that Ventura, having been carried off the field, couldn't go back and run the bases to get credit for the grand slam.

"I can remember years ago, during World War II, a game at Yankee Stadium. Bobo Newsome was batting for the Philadelphia A's . . ."

So began an anecdote, the culmination of which was a rule preventing a batter from rejoining the field of play once he's gone to the dugout.

Seymour Siwoff, president of the Elias Sports Bureau, the official statisticians for Major League Baseball, was watching the game on television when he saw the grand slam/single. He immediately called the office and asked the person who answered the phone, "Did you see what I saw?" Yes, the bureau knew: It couldn't be a homer.

Baseball is as rule-intensive as any sport ever invented, including cricket. Just take a gander at the rules online (at www.majorleaguebaseball.com), and you'll see that this is a game supervised by pathologically persnickety individuals. Unforgiving, punitive, Procrustean, the anonymous scribes of the rule book are also imaginative, anticipating the most complicated and bizarre scenarios and then adjudicating their proper outcome. (You might find entertaining the very long discussion of what to do when an "improper batter" comes to the plate rather than a "proper batter.")

Several rules seem to apply to Sunday night's situation. One is pretty basic: 6.09(d) states, "A fair ball passes over a fence or into the stands at a distance from home base of 250 feet or more. Such hit entitles the batter to a home run when he shall have touched all bases legally."

Ventura didn't touch all the bases, legally or otherwise.

The second rule that applies is 10.07(f), governing game-ending hits. I'll quote the whole thing, but you can skip to the "Note" if your eyes are glazing over:

"Subject to the provisions of 10.07(g), when the batter ends a game with a safe hit which drives in as many runs as are necessary to put his team in the lead, he shall be credited with only as many bases on his hit as are advanced by the runner who scores the winning run, and then only if the batter runs out his hit for as many bases as are advanced by the runner who scores the winning run. Note: Apply this rule even when the batter is theoretically entitled to more bases because of being awarded an 'automatic' extra base hit under various provisions of Playing Rules 6.09 and 7.05."

To explicate this tedious situation: This is a rule that typically applies when a batter hits a game-winning "ground rule" double (the rule book is so pervasive that some hits are actually named after rules!). That's when the ball lands fair but bounces out of play. The batter has to run all the way to second base if he wants credit for the "automatic" double; otherwise, he gets credit only for a single.

Finally, 10.07(g) states: "When the batter ends a game with a home run hit out of the playing field, he and any runners on base are entitled to score."

Note the word "entitled." It means that scoring is his option should he choose to round the bases even though the game is already won.

I asked James Cargile, a philosophy professor at the University of Virginia, if it makes more sense to call the hit a grand slam--which it appeared to be--or a single, which it officially is.

"If you're speaking with the vulgar, you could call it a home run," Cargile said. But he added that the rules seem to have fully anticipated such a situation, so it's not that complicated as a matter of philosophy.

"It's an interesting case, but not a deep problem case. A deep problem case is when the rules are defective," he said.

Siwoff, the statistics-meister, scoffed at my lame suggestion that perhaps the rules could be fudged a bit to give Ventura credit for a grand slam.

"You can't! It's the rule!" he said. "A rule is a rule. You can't arbitrarily decide emotionally, 'I think I'm going to give him this grand slam.' You can't!"

This runs deeper than mere baseball, he suggested.

"If we didn't have rules, we'd have an awful lot of traffic accidents, wouldn't we? Think of it, people are constantly not obeying the traffic rules. They double-park, they pass red lights, they do all these things. Rules are important. They're a discipline. Without a discipline, you have no game. You can't make it up as you go along."

Ventura handled it just right. He said it didn't matter. He won the game. He showed a becoming humility in not worrying about such silly things as statistics.

So, there was no grand slam. But, by gosh, it was a grand single.

This edition of Rough Draft has been officially scored as a "wild pitch." The column appears at 1 p.m. on Monday, Wednesday and Friday as part of the PM Extra edition of washingtonpost.com.