During a global rock-music revolution, she was a conduit to AM radio and the Top 40 airwaves. And despite CKLW's Canadian home base, the station was regarded in the industry as a Detroit outlet.
"Basically (Detroit) was becoming known as testing the true rock 'n' roll records," Trombley said.
She also took cues from black radio in Detroit, helping break artists such as the O'Jays and the Foundations to pop audiences. In 1971, she was among the first programmers who helped make a hit out of Marvin Gaye's "What's Going On," a record initially resisted by Motown chief Berry Gordy.
In 1974, when she heard Detroit R&B station WJLB spinning an Elton John album cut, Trombley added the track to CKLW's rotation. "Bennie and the Jets" instantly ignited the station's request lines, and John's record label was soon convinced to release it as his next single.
"A week later, Elton called her from England and wanted to know the whole story," son Tim Trombley said.
Trombley's veto power was as important as her thumbs-up, and that make-or-break influence was immortalized by Seger in the vaguely sardonic 1973 tribute "Rosalie": "She's got the plastic/ It comes from all the corners of the world/ So fantastic/ She's everybody's favorite little record girl."
But Trombley, who once called herself "a lyric freak," was a bona fide Seger fan, embracing his music for the CKLW airwaves.
"It didn't matter what it was by Bob," she said. "He didn't miss too often."
Seger and Trombley ultimately forged a friendship, often meeting up at Windsor's Hacienda restaurant to talk music. Their connection, she said, came from their similar, low-key personalities.
"I always felt comfortable around an artist that I could trust, that would respect the privacy I kept in my private life," she said.