The biggest thrill of American Ballet Theatre's lavish opening night at the Wang Center Monday was watching Mikhail Baryshnikov and Elaine Kudo in ''Sinatra Suite.'' At times, Twyla Tharp's brilliant choreography is a violent rehash of standard ballroom dancing and assorted romantic cliches. It is also a compelling romance. The dancers don't act; instead, they seem absorbed in foxtrotting around under the dark, gooey shellac of Frank Sinatra's voice, intoning ''Strangers in the Night.'' The story is in the choreography.
The dancers move so smoothly you never see the sole of a shoe, but they keep zipping off in different directions. As they glide, you see the flick of a head, the shift of a back, and you feel they are in silent, intense negotiation about where to go next. There is always the tension about who will lead and who will follow. One partner pulls away until the other reluctantly turns and closes in. The dance has a highly polished surface, but you feel that no move is taken for granted. Every step is a decision, and when their feet follow each other it seems miraculous.
To ''That's Life,'' they break into a sort of apache dance, where the male partner brutally throws the female around. The turns and under-arm swings get tangled. Baryshnikov moves abruptly, as if furious. He begins the jitterbugging stunt of pushing the woman down and through his legs, but he gets Kudo folded upside down and then just leaves her in a heap. Sometimes he shakes her vigorously to the music, and he turns her by putting his hand on her head as if it was a knob, as Sinatra croons ''I Did It My Way.''
It's not so much a fight between a brute and a vulnerable woman as a contest between speed and weight. As Baryshnikov thrashes, Kudo counterbalances him. At one point she stiffens and falls over sideways against him, forcing him to catch her. When he pulls, she leans away as if to yell ''Whoa!'' It looks like a fair fight.
The ''romance'' ends with a solitary Baryshnikov, and it is a credit to his and -Kudo's partnering and Tharp's shrewd choreography that for once I was sorry to see him alone on stage. ''Sinatra Suite'' will play again tonight at the Wang Center. ''Cinderella,'' a full-evening story ballet, comes Friday and Saturday.