Olga Korbut's career as a competitive gymnast has ended, in a sniffle and a sneeze.

Korbut, the tiny one with the flexible physique and ear-to-ear smile, turned the world on to what had been a pretty obscure sport (if that's what it is) with her 1972 Munich Olympic triumph. Consistently, outscored since by conpatriots Ludmilla Tourisheva and Nelli Kim and eventually overshadowed by Romania's Nadia Comaneci, she still captivated the crowds on tour to the last. She was scheduled to make a farewell appearance with the Soviet officials sent word she was in-bed with the flu in Moscow and will not compete again.

Korbut, a 22, plans to return home again. Grodno near the Polish border and next month marry a comrade who Soviet officials called a "pop star." Then she will go into coaching.

Let's hope we can always say what President Richard M.Nixon told her when they met: "I have always been impressed with your ability to land on your feet" . . .

Mean Joe Greene, the Steeler tackle, was called onto Pete Rozelle's New York carpet for a Monday confab about the 280-pound Pittsburgher's tirade last week in which he wished NFL game officials all the worst. Yesterday, sentence was pronounced: fine, Undisclosed, but figure on $1,000.

Other folks passing awards to each of their batboys were bitter over being blanked when the Yanks split World Series booty - screamed and later were given $100 pittances from a "players' fund." Only one of last year's batboys was back on the job this year - not the two most vocal with the "cheapskates!" complaint. P.S.: Preliminary estimate is that each Yankee player will receive $32,000 as his series winner's share . . .