Once Kings?

They stood like titans over their respective music worlds, sold albums in garish, record-breaking numbers and earned the shorthand of true celebrity--they needed only their first names to be identified.

Michael. Garth.

The King of Pop and the King of Country. The Glove and the Hat.

And now they are reentering the music arena with new albums after extended absences. But in the current landscape of gold-toothed rappers and teen pop queens, where do these veterans fit?

Michael Jackson put out his last album of new material in 1995, and he’s nearly two decades removed from the incandescent success of “Thriller.” The conventional thinking is that he is known to young pop fans today more as a tabloid caricature than as a contemporary hit-maker. His new album, “Invincible,” from Epic Records, hits stores Tuesday.

Garth Brooks also put out his last full album of new material in 1995--that’s if you don’t count his ill-fated experiment to present himself as a fictitious pop singer named Chris Gaines. That 1999 album, planned as a tie-in to a movie that never happened, flopped by Brooks’ lofty standards (it sold 1.1 million copies, a fifth of his usual efforts). He followed the Gaines effort with a retirement announcement, perhaps further confusing his fans. His new album, “Scarecrow,” arrives on shelves Nov. 13 from Capitol Nashville.

There are few similarities in the sounds of the two stars, but their histories make them instant topics of interest for the music industry and its oddsmakers. The buzz: The Oklahoma-born country star, with a strong new radio hit and more recent successes, is less a gamble than the reclusive Moonwalker.

“I don’t see it as being as long a gap for Garth as Michael,” says Geoff Mayfield, director of charts for Billboard magazine, the music industry trade. “And Garth has a consistent sales pattern over the past decade. Garth was No. 1 more than any artist in the [album chart] in the 1990s, and we’re not that far removed from the 1990s. Radio has been starving for him.”

The appetite for Jackson is more difficult to gauge, but the singer clearly has a powerful curiosity factor at work. Jackson’s eccentric ways and life story make it certain that his videos will get a first look from even casual followers of celebrity. Rick Krim, a top programming executive at VH1, says it was a “no-brainer” for the cable channel to devote significant air time to Jackson’s return. “Because of who he is, there is a strong and immediate interest in anything he does,” Krim said. “Whether it goes beyond that initial curiosity will depend, of course, on the music itself.”

The music on the long-awaited “Invincible” is still tightly under wraps, but The Times’ pop music critic, Robert Hilburn, in a review to be published Sunday, says the new disc offers some inspired moments but has long stretches that are “sappy, derivative and labored.” However, Jackson’s supporters predict the new material will connect strongly with fans. “It is going to be exciting and set new standards,” predicted Frankie Blue, a New York radio programmer and Jackson confidant.

Sources within Sony Music, Epic’s parent company, predict that Jackson will have first-week sales between 300,000 and 400,000 copies, meager compared to his 1980s heyday but certainly respectable. His last album was “HIStory: Past, Present & Future” in 1995, a two-disc set that was half greatest hits and half new material. That package sold 391,000 in its first week and went on to sell 2.4 million copies.

By comparison, top-selling acts of today, such as Eminem or Britney Spears, have posted first-week totals of more than 1 million copies.

Brooks has been a member of that million-a-week club before and has a major country radio hit setting the stage for “Scarecrow.” His “Wrapped Up in You” has just posted the second-highest debut in the decade-long history of a Billboard chart using a computerized system to track airplay at U.S. country stations. (The top debut performer ever on the chart? Brooks’ “The Thunder Rolls” in 1991.) That radio presence might help Brooks hit a commercial home run, the way his “Double Live” concert album did when it sold 1.1 million copies in a single week in 1998.

“If anyone is a candidate to sell a million copies in a week this year, it’s him,” Mayfield said, although most observers predict this Brooks effort, arriving with less fanfare than “Double Live,” will perform strongly but remain well in the six-digit realm.

The country music market is sagging, with some of its biggest stars, including Shania Twain and Faith Hill, on the sidelines for the moment. Depending on how you look at it, that sets the stage for Brooks to either make a big return or run into overly intense scrutiny from a jittery Nashville.

The sound of country music has shifted toward pop in recent years, notes Lon Helton, country music columnist for Radio & Records, a trade publication. “The labels have sought to sell more records by going outside country radio to get listeners, and to get those stations, you have to tip a little more to a pop sound ... and here comes Garth into that,” he says.

Not that Brooks is a stranger to pop sensibilities. He has often cited James Taylor and Billy Joel as favorite stars with a strong sway on his own creative compass, but excluding the Chris Gaines project, Brooks has also kept a twang in his work. His new album reportedly goes further toward country roots, which will separate it from much of Nashville’s current big-name product.

“Garth has expressed some wonderment about whether what he does even fits in today,” Helton said. “He says he doesn’t like the music on country radio today and that he wasn’t sure if he wanted to participate.”

Pat Quigley, the former chief of the Capitol Nashville label, worked closely with Brooks on some of his biggest successes before he left Nashville to work with Dataplay, a new mini-disc technology company.

“I do think, in a way, he has to reintroduce himself,” Quigley said. “I don’t think Garth is ever one to sit around and worry about radio. But does his sound still fit in with country music fans? That’s a legitimate question for Garth.”

If Brooks is looking to tradition, Jackson is seeking to update his sound. Jackson brought in hot young producer Rodney Jerkins to help craft “Invincible,” and he used an appearance with ‘N Sync at the MTV Video Music Awards and television commercials on Nickelodeon to present himself to younger fans.

His lead single, “You Rock My World,” enjoyed a flurry of radio interest on release but is now dropping on the Billboard Hot 100 airplay chart. That’s not the case, though, overseas. Veteran U.S. superstars often find more loyalty and excitement from fans in foreign markets, and “You Rock My World” is a smash in Spain, Belgium, Italy and beyond, suggesting that Jackson’s return will play well abroad.

That’s no surprise, says the singer’s attorney, John Branca, who notes that “Thriller” may be the second-best-selling album in U.S. history (its 26 million narrowly trails the Eagles album “Their Greatest Hits 1971-1975” with 27 million), but it can’t be beat in the global market.

“Worldwide, there is no album within 30 million units of ‘Thriller,’ ” Branca said. “It’s untouchable. It’s sold 60 million units worldwide. Michael can’t be rivaled when you look at the world. And that hasn’t changed.”