She made her sensational debut at the Metropolitan Opera on 6 December 1941 in a broadcast performance singing Sieglinde in Wagner's "Die Walküre", substituting for the indisposed Lotte Lehmann with almost no rehearsal. This was her first appearance in a leading role, and it was a triumph. Six days later she replaced the ailing Helen Traubel as Brünnhilde in the same opera. Varnay and Weigert became closer and were married in 1944. It was also at this time that she had lessons with former Metropolitan Opera tenor, Paul Althouse.