For Enrique Mazzola , the path to the conductor’s podium began when he was a boy in the children’s chorus of the Teatro alla Scala in Milan.

“Backstage, there were all these monitors showing the conductor conducting, used by the stage managers,” Mr. Mazzola, who was announced on Thursday as the next music director of Lyric Opera of Chicago, recalled in a telephone interview.

“I was fascinated,” he said. “I would spend hours and hours watching the conductor.”

Now, after distinguishing himself with stylish, energetic performances of bel canto operas, French repertoire and early Verdi, he will succeed Andrew Davis, who plans to conclude his two-decade tenure in Chicago at the end of the 2020-21 season.

It will be a major changing of the guard at Lyric, which has been struggling, like many opera companies, to survive as audience habits shift, and which went through a brief musicians’ strike last season. Mr. Davis, who has conducted 674 opera performances and been music director since 2000, said he had initially planned to step down after conducting Wagner’s “Ring” cycle in the spring, but agreed to stay on one more season.