At last the Metropolitan Opera has made it to the stage of the Kennedy Center. Last night, bringing one of the world's superstars to brighten the proceedings, the Met opened its week-long run in the Opera House with Donizetti's "L'Elisir d'Amore."

Luciano Pavarotti was on hand to sing "Nemorino," a role tailor-made for his finest talents. And what a good thing for the production that the great tenor was there. Because Donizetti's "Elisir" is a slender flower, one that easily wilts on the vine. There is exactly one familiar aria in its entire course, even though there are streams of melodies for one, two and three singers, and plenty of chorus passages.

The curtain went up around 8:10, but it was not until 1:30 that the kind of fire that keeps opera houses warm around the world was kindled. That moment occurred when Pavarotti ambled to the center of the stage and gently worked his way through "Una furtiva lagrima."

Earlier, however, he had been the central figure every time a scene took on some life. He has a wonderfully individual Nemorino gait, a kind of happy hop that expresses a barely repressed glee. Time after time, it was he who suddenly lifted the whole affair out of kind if prim but stodgy routine. Perhaps the reason for the tedium lay in the fact that the company had not put the opera into production until last Thursday night in New York. This was its second performance.

Pavarotti was surrounded by an able company but one that, aside from Judith Blegen's Adina, lacked any real distinction in singing. Blegen's voice is lovely and she handles it beautifully. Nevertheless there is a kind of restraint in her portrait, almost as if she really could not take all that foolishness seriously. Mario Sereni's Sergeant Belcore is without any vocal or dramatic polish. Domenico Tremarchi has much of the best basso-buffo routine for Doctor Dulcamara and knocked off his patter song with Adina in fine style. His entrance, as he was borne in under a huge balloon, delighted the audience.

Loretta Di Franco sang Giannetta as well as could be imagined.

Nicola Rescigno conducted with style, but often there was not the ultimate coordination between stage and pit -- again perhaps because the piece is not yet set. It was a safe reading.

"L'Elisir" is a pleasant, simple, old-fashioned opera. Nathaniel Merrill's production did nothing to upset Donizetti's aims but David Sell's direction was a pretty flat business. The sets and costumes of Robert O'Hearn were in the same conventional mold. Had the lighting cues worked, Gil Wechsler's designs would have been adequate.

All in all, it was not a great evening, aside from some of Pavarotti's singing. With tonight's "Otello," things move into high gear, musically speaking.