Zach Johnson had to defend himself, a peculiar position for a guy who had just finished a two-week stay in Hawai'i by playing his final six rounds in 30-under par and winning the Sony Open for the fifth victory of his career.

No one questions the caliber of his golf.

It was his height, which the PGA Tour media guide lists as 5-foot-11.

"That's about right," Johnson said, feigning surprise when he heard laughter. "OK, 5-10 — maybe 5-10½. You don't think I'm 5-11?"

Whatever the actual measurement, he always seems to play a few inches taller.

Sunday was yet another example. Tied for the lead with David Toms as he made the turn, Johnson seized control of the Sony Open with a 5-iron into 4 feet on the 11th to take the lead for good, a 7-iron to 8 feet on the 14th for another birdie, then two flawless swings on the closing hole to reach the par 5 in two and secure the fifth victory of his career.

Five victories, including the 2007 Masters when he held off a charge from Tiger Woods, might not seem a lot to some. But remember, Johnson didn't attend college at a golf factory. He went to Drake. And when he graduated, he toiled for six years on some tours that no longer exist until he finally made it to the big leagues.

He was asked what he would have said had someone told him when he left college he would have five PGA Tour victories and a major.

"What are you on?" Johnson said to more laughter.

"I was very raw," he said. "Always a decent putter, but I was never very consistent with any part of my game. If someone would have said that, I would have said ... I wouldn't have believed them. There's no way I would have believed them."

Does that make him an overachiever?

Yes, and he's proud of it.

"That's my upbringing," Johnson said.

He isn't the only one who has overachieved from Cedar Rapids, Iowa.

On Sunday, Johnson wasn't even the biggest overachiever from his own high school.

He was four years behind quarterback Kurt Warner, who led the Arizona Cardinals to their first Super Bowl just about the time Johnson was teeing off with a one-shot lead at the Sony Open.

"A good day for Iowa," Johnson said.

Someone reminded him that Warner took more hits Sunday than Johnson, and the golfer replied that Warner was bigger.

There's that word again.

Johnson says he is 170 pounds — about 10 pounds more than he would like — but you have to wonder how much of that is heart. That's what it takes to roam the country on circuits called the Prairie Tour, the Teardrop Tour, the Dakotas Tour, and to such remote towns that it would be easy to quit.

He not only persevered, he has played in the Ryder Cup, the Presidents Cup, and has earned over $13 million in the last five years.

"He's a good player, and tough to beat," said Toms, who did everything he could to chase him down and still finished two shots behind at the Sony Open, along with Adam Scott.

Maybe it was just a coincidence, but Johnson had dinner Saturday night with Corey Pavin, the next U.S. Ryder Cup captain. Pavin for years was known as the "gritty little Bruin" from his days at UCLA, and there are some similarities.

Neither will ever be mistaken for a power player. Pavin is listed as 5-foot-9 — that's debatable, too — but managed to scratch out 15 wins, a U.S. Open title and appearances on three Ryder Cup teams during the era of Greg Norman, Nick Faldo and Nick Price.

"I am not Corey Pavin — far from it, especially when you're talking about a resume," Johnson said. "However, maybe some parallels are there as far as our stature, and certainly how we play the game and how we compete. I don't know what sets me apart at times, but competition is what drives me.

"It really doesn't matter what it is," he said. "I want to win."

Johnson struggled last year to live up to his status as a Masters champion, which is not usual. He didn't make it out of the first round of the FedEx Cup playoffs, and there was some question whether he would finish in the top 125 on the money list. But the forced break in September allowed him to evaluate where he was going, and he wound up winning the Texas Open a few weeks later.

In some respects, his 2009 season started toward the end of 2008.

With those two victories, coming six tournaments apart, he now has won in each of the last three years. That doesn't put him in the same league as Tiger Woods, Phil Mickelson and Vijay Singh, but it's more than he would have believed.

"Obviously, this one is sweet — the sweetest one I've had because it's right now," Johnson said. "I think this game is getting hard and harder as far as talent, and it just makes me want to work harder. I'm going to make it hard, and I'm going to work hard at it, and I'm going to practice."

Where does that put him? Johnson would rather others make that call.

"I just know that my game is going the right way," he said, "and I'm excited about the future."