Tenor Marcus Haddock's father was a traveling Baptist preacher. Though young Haddock was born in Fort Worth, Texas, he was raised in numerous west Texas towns surrounding Lubbock.

Indeed, the internationally acclaimed Haddock, who makes his San Diego Opera debut Saturday night in Puccini's "Tosca," first found his voice as a church cherub. As a high school senior in Seminole, he played Conrad Birdie in "Bye, Bye, Birdie."

Haddock's speech is so precise that his Texas twang becomes apparent only in fervent moments when he speaks of such things as Kathleen, his wife of 25 years, the beauty of their upstate New York home in Skaneateles, and his busy international career.

"I was just a boy in Texas," he says. "My jobs in the summer were working on a farm. I never, ever dreamed I would leave the United States."

Leave he did, after obtaining a degree from Boston University, studying with former opera star Phyllis Curtin and a win in the 1984 Metropolitan Opera National Council Auditions. Shortly thereafter, he flew to Budapest to sing.

"I was wide-eyed and they knew it," he says with a chuckle.

Then Haddock sang in Italy, France and Germany, and in 1988 took a house contract in Aachen, Germany, thereafter moving up to opera houses in such cities as Karlsruhe and Bonn, where he sang Casio to Placido Domingo's Otello in the Verdi opera.

When Haddock returned to the States after eight years abroad, Domingo cast him as Ruggero in Puccini's "La Rondine" at Washington National Opera, where he appears regularly.

"(Domingo) gave me great and numerous opportunities during the past 13 to 15 years," said Haddock, who has gradually and carefully moved into the heavier roles.

"I was able to master the coloratura (of Rossini), but the voice started moving and changing through the years, which is often the case." If lyric tenors are cautious, the voice becomes more lirico-spinto (of a weight between lyric and dramatic) as they age, and they are able to sing Verdi and Puccini roles.

There are roles Haddock still wants to add to his repertoire, some of which he has discussed with Ian Campbell, San Diego Opera's general and artistic director.

"Yeah, we have … we will … eventually, I will," Haddock says, apparently unwilling to be more specific. For now, Mario Cavaradossi (his character in "Tosca") will do.

Chock-full of passion and some of Puccini's most ravishing arias, "Tosca" is set during a time of political turmoil. Rome is literally a police state.

Haddock's character, painter Mario Cavaradossi, is painting a portrait of Mary Magdalene in Rome's Sant' Andrea della Valle cathedral. He is in love with opera singer Floria Tosca (French soprano Sylvie Valayre in her San Diego Opera debut).

Baron Scarpia (American bass-baritone Greer Grimsley), chief of the secret police, lusts for the diva. When Mario is arrested and tortured for hiding a political prisoner, Scarpia offers Tosca a deal: If she satisfies his lust, he will make certain that the guns used for Mario's execution are loaded with blanks.

"Politically and emotionally, Cavaradossi is quite focused," said Haddock, "especially in this matter of a revolution, wanting an Italian republic, trying to get rid of tyrants; but he's young and arrogant, and in his youth feels he can stand up to Scarpia and get away with it. He's madly in love with Tosca, understands Scarpia is dangerous and despicable and is hopeful things will change for his country. He doesn't realize that things are going to go badly for him."

Things are going well for Haddock, who expected West Texas and got the world.

"At one point long ago," he says, "I thought I would buy some land, be a farmer, raise cotton and maybe have some cattle."

There's time for that later, no? "It's a little late now. I think I've forgotten how to drive a tractor."

"Tosca"

When: 7 p.m. Jan. 24 and 27; 8 p.m. Jan. 30; 2 p.m. Feb. 1; 7 p.m. Feb. 4

Where: San Diego Civic Theatre, Third Avenue at B Street, San Diego

Tickets: $35-$200

Phone: (619) 533-7000

Web: www.sdopera.com