Luke Donald goes into the U.S. Open ranked No. 1 in the world, and to listen to the casual golf observer, that can only mean one thing.

There must be a better system.

Luke Donald?

He is not an imposing figure like Vijay Singh or Ernie Els. He doesn't have a personality that can take over the room like Greg Norman or Seve Ballesteros. He doesn't have 14 majors like Tiger Woods, or any majors at all, for that matter.

There is little about Donald that looks like the No. 1 golfer.

He just plays like it.

"There's always going to be people who look at my game and say, 'He's No. 1?' That's just the way is," Donald said. "Whether they do or not, I don't really focus on that. I focus on what I can control, and that's just working hard. But I think I'm forcing people to respect me now. It's getting to that point that I'm not going away."

To look at the golf — and not just the golfer — there should be little question.

Donald has won six times in the last 18 months, more than any other player in the world. When his only option was winning, Donald birdied six straight holes to start the back nine Sunday at Disney, a clutch performance with historical significance. That win allowed him to become the first player to capture the money title on both sides of the Atlantic in the same season.

Even so, when U.S. Open champion Rory McIlroy first went to No. 1 in March by winning the Honda Classic, there was a feeling the 23-year-old from Northern Ireland would stay there. Three times since then, Donald took it back, twice by winning.

Perhaps a U.S. Open title at Olympic Club would help change the perception. Or maybe not.

"I think the public wants a No. 1 like Phil (Mickelson), Tiger or Rory," Stewart Cink said. "Luke is a nice, unassuming guy. He gets it done with his putting, with his short game, with his wedges. That's not the dramatic stuff a lot of people want to see. They want to see the long ball. They want to see Tiger making dramatic putts."

But is it the stuff Donald's peers wish they had?

"Shoot, yeah," Cink said. "The ones who play do, not the ones who watch. But that's why they're watching."

What makes Donald's rise to No. 1 so remarkable is that for so many years, his performance was barely above ordinary — and perhaps that's why some people struggle to give him his full measure of respect.

Lee Westwood is the only other player to be No. 1 without ever having won a major. But he reached No. 4 in the world early in his career, he won the Order of Merit in Europe at age 27 and was seen as a potential threat for years to come until he was derailed by a slump.

That was never the case with Donald. For most of his career, he was regarded as a mild-mannered Englishman who won an NCAA title at Northwestern and majored in art.

This, however, is not the same Luke Donald.

"He was the same player for 10 years," Geoff Ogilvy said. "He made a slight improvement, as people do when they get older. But two years ago, he obviously made a conscious decision that, 'I'm going to do things differently.' Whatever it was, it was a big difference. Because he's clearly the best player."

The 34-year-old Donald began changing after he had to miss the second half of 2008 with a wrist injury, brought on by trying to hit the ball farther. In one of the tougher decisions, he decided to replace his brother as his caddie with John McLaren. Even more pivotal was bringing in Dave Alred, a performance guru from Britain who is famous for working with rugby players such as Jonny Wilkinson.

Wilkinson wanted Donald to be a killer on the golf course.

"I suppose I lacked a little ruthlessness," Donald said. "That was my nature, coming from England. Dave wants me to be the hunter, not the fisherman. He talks about how a fisherman throws it out there and hopes to get a fish. A hunter goes out there and he's going to go straight between your eyes. That's the vibe and feel Dave is after.

"He wants me to be that assassin," Donald said, pausing to smile. "And I'm trying hard for him."

McLaren recalls the time years ago, before he went to work as his caddie, when he was in Chicago and stayed at Donald's apartment. He heard him talk about his aspirations, perhaps one day being No. 1 in the world.

"I remember thinking it was ambitious, to say the least," McLaren said. "The game we know that Tiger Woods created, you wouldn't think someone of Luke's athletic proportions could be No. 1. We're so used to the very best in any sport being big characters, big athletes. I always thought he'd be up against that."

But when he first caddied for Donald in 2010, he noticed a different player, a different person.

"I suppose the biggest shock for me was how tough he is," McLaren said. "He can be quite cutting at times. When we first started, I thought, 'Hmm, you've got a streak in you I didn't know you had.' I always thought he was very unassuming. Luke is fiercely competitive. He hides it well by being very English. He's well educated, well brought up. The fire burns, he just doesn't let anyone know it."

McLaren got another glimpse of that when McIlroy went to No. 1 at the Honda Classic, and Donald became yesterday's news. It was natural for attention to shift to McIlroy, especially after his record-setting win at the U.S. Open the previous summer at Congressional. Then, McIlroy came out of nowhere with a 65-67 weekend at Doral and nearly won a World Golf Championship. This was McIlroy's time.

The next week, Donald shot 66 at Innisbrook and hit a clutch shot out of the rough to win a playoff.

He was right back at No. 1.

"Rory goes and wins the U.S. Open by eight shots, and everyone stopped talking about Luke," Ogilvy said. "And he was like, 'Hold on, here I am,' and he goes and wins another tournament. And he's been doing that for 12 months, hasn't he? Every time the question has been asked, he's answered it."

One major question remains.

Donald made a strong bid at the Masters last year and tied for fourth. That's as late in the final round as he has ever contended in a major. He has shown mettle at other tournaments, such as beating Westwood at Wentworth in a playoff last year to first get to No. 1, closing with 64 at Disney in a rare do-or-die moment in golf. His win at the Match Play Championship last year remains the most ruthless performance ever at that event. In six matches, Donald never trailed once and never reached the 18th hole.

"I've won some big tournaments over the years," Donald said. "I'm figuring out the majors. I'm hoping I'll be like Ben Hogan and win eight after I'm 35. I'm really starting to figure out myself, how I deal with pressure. I'm getting a lot closer. I'm finding ways to win tournaments, and hopefully, that will carry into winning majors."

Mickelson won his first major at 33. Padraig Harrington won the first of his three majors at 35.

"For a lot of years, the Tiger factor fooled us into thinking you come out at 20 and dominate," Adam Scott said. "That last happened in 1962 (with Jack Nicklaus). Greg Norman dominated the game in his 30s and 40s. Ben Hogan didn't win a major until he was 33. Some players mature later. Some people peak at 18 and never get any better. Luke is a bit of a grinder. He has stepped up his game and found out what worked. It's clear in my mind that right now, he's the best player in the world."