JACKSONVILLE, Fla. (AP) -- So much about Shane Lowry's victory in the Irish Open was surprising.

The burly, 22-year-old Irishman was only the 16th-ranked amateur in the world, hopeful of making the Walker Cup team, when he teed it up for the first time on the European Tour. His 62 in the third round matched the lowest score ever by an amateur on the tour. His playoff victory moved him up to No. 168 in the world, 14 spots better than Colin Montgomerie.

That Lowry won a European Tour event as an amateur? Not so surprising.

As much as his victory in the wind and rain on the links of County Louth was cause for celebration, it raised questions about the strength and depth of fields on the European Tour.

Lowry became the third amateur in the last two years to win on the European Tour. He joins Spain's Pablo Martin, who won the Portugal Open in 2007 a week before the Masters; and 18-year-old New Zealander Danny Lee, who captured the Johnnie Walker Classic in Australia three months ago to become Europe's youngest champion in history.

That raises questions when compared with the PGA Tour, which is going on its 19th consecutive year since its last amateur winner, Phil Mickelson in 1991.

"On this tour, a lot of it has to do with the depth of the fields," said Scott Verplank, who preceded Mickelson when he won the 1985 Western Amateur as a university student. "Not to take a sideswipe at the European Tour, but I think there's something to that."

Mickelson was also at university when he won the Northern Telecom Open in Arizona by one stroke over Tom Purtzer and Bob Tway. Since then, no amateur has even come close.

A year after Mickelson's feat, David Duval was a 20-year-old amateur when he had a two-shot lead over Tom Kite going into the final round of the BellSouth Classic in Atlanta. He closed with a 79.

"I was naive and young and didn't know what it was entirely about," Duval recalled on Tuesday. "I just knew I was playing well. I remember that I got asked if I thought I could beat Tom Kite, and I said, 'I don't know. I've beaten him so far.' I got in trouble for that one for being arrogant. But I was beating him. Was that a bad answer?"

Ty Tryon was 16 when he spent more time chasing the leaders than the cut line at the 2001 Honda Classic, eventually tying for 39th. Most recently, Tadd Fujikawa was 16 when he entered the final round of the Sony Open six shots out of the lead and tied for 20th.

"There's a lot of good, young kids coming along," Verplank said. "That it happens three times in Europe over the last couple of years, you could construe that as another show of strength of our tournaments compared with everyone else's. But that's nothing against the amateur players. The best amateurs from around the world are as good as the best in the United States."

He certainly had no qualms with whom Lowry beat -- Padraig Harrington, Rory McIlroy and Lee Westwood were among those who teed it up in the Irish Open, the highest-rated tournament in golf last week.

Likewise, Lee beat a group of players in Australia that included Westwood, Anthony Kim, Camilo Villegas and Ian Poulter.

Verplank and Mickelson were among the best amateurs when they won as amateurs. Martin and Lee have a similar pedigree.

Martin first showed his stuff at age 17 when he was the 54-hole leader at the Spanish Open. He was named the top U.S. college golfer.

Lee was born in South Korea and groomed for golf in New Zealand. After supplanting Tiger Woods as the youngest U.S. Amateur champion, he made his PGA Tour debut last August at the Wyndham Championship and shot four rounds in the 60s to tie for 20th.

Lowry might have been the most unheralded of the three, although he was well-known in European golf circles. The Irishman now has to decide whether to stay amateur and compete at the Walker Cup, or cash in by turning pro.

Martin has not had a top 10 since he turned pro and now is No. 527 in the world. Lee has missed four cuts in the six times he has played since winning in Australia.

Perhaps Lowry should consider what Mickelson told The New York Times a few days after he won as an amateur.

"It was unbelievable to me how, as soon as the tournament was over, everybody was hurrying to catch a flight for Hawaii," Mickelson said. "I was so drained and so tired. There was no way I would have been able to play this week. That's why right now I don't feel that I'm ready to turn pro and play every day, week after week."

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