Broadway doesn't usually heat up till autumn leaves start to fall, but this year -- thanks to the joyful arrival of Warren Leight's Side Man at the Roundabout in June -- we now have a solid yardstick to judge other dramas that'll be coming down the pike this season. This wise, wistful, often witty "memory play" focuses on the nose-diving decline of Big Band jazzmen and its devastating effect on a family. A crack ensemble, ferociously funny and intrinsically sad by turns under Michael Mayer's skilled direction, hit all the right notes on stage -- and, afterward at the opening-night party at the Millennium Hotel, danced the night away to the highly apt Big Band sounds of Howard Williams's jazz orchestra (Leight's idea, of course).

Side Man's gold-hearted girl-on-the-side brings Angelica Torn to Broadway where her father (Rip Torn) fell in love with her mother (Geraldine Page) doing Sweet Bird of Youth. Papa, beaming from ear to ear over the debut, sent opening-night flowers "from Gerry and me."

Robert Sella, the Leight facsimile in the play, and girlfriend Enid Graham qualify as an award-winning couple these days: He won the Helen Hayes Award for Washington D.C.'s four-hour (from seven) Mourning Becomes Electra, and she got a Theatre World Award for Broadway's Honour.

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William Finn set his own medical nightmare to music for A New Brain, and, to play a musical-comedy variation of himself-as-impatient-patient, he got Malcolm Gets, on hiatus from "Caroline in the City." Said Finn: "Malcolm knows how to treat a lyric, nobody can make a joke better, and his voice goes all over the place, so he's very easy to write for." Gets, too, thought it a good fit: "I hate to say it, but I relate to his neuroses." *

Less literally and less tragically, Labor Day allowed A.R. Gurney to put himself into a play -- a playwright mining his family for dramatic material -- and Josef Sommer played the part to a T (or is it a G?). In three years -- in 2001 -- Gurney will mark his 50th year as a playwright. Word just in from Williamstown is that one of his best -- Far East -- has opened there.