From an epidemiologic standpoint, this year is different from 1984: apparently pennant fever evolves between outbreaks, in much the way that viruses change every time it seems they’ve been trapped and eradicated.

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Still, the disease’s last phase remained the same. In 1984, after the 81st game had been played at Wrigley Field, three-quarters of the fans refused to leave the park until the team–many of whom had already begun to change from their uniforms–returned for a delirious extended curtain call, which consisted of strolling the playing field and basking in the cheers and thanks of the crowd. Only three of the current Cubs were around for that extraordinary show of support, which would be unimaginable in nearly any other city; consequently, when last Sunday’s home finale ended with a similar display of adulation, almost all the players were genuinely amazed and gratified by the scene around them. They simply hadn’t seen this symptom before.

(Meanwhile, from the stands and the rooftops and the TV screens around town, the delightful irreality of the 1989 Cubs topping their division was enhanced by the patently incongruous sight of half-undressed ballplayers loping around the outfield to wave at the crowd–a sight akin to actors returning to the stage when the play is ended, dripping makeup, out of character, and proceeding to converse with the remaining theatergoers as if they were in fact equals in the preceding drama.)

Each series this month has yielded such moments, and one would be hard pressed to name a turning point. The sweep of the Expos, which effectively punctured their most fantastic remaining hopes? The above-mentioned Kilgus performance, the fulcrum game on which turned last weekend’s sweep of the Pirates? Or (as I suppose most people will suggest) the weekend of September 8, when the Cardinals brought their legions of red-clad supporters to Chicago, turning the ballpark into a college football stadium, with each team’s scores wringing equal cheers and chants from the crowd–only to watch the Cubs take two of three?