Since Tiger Woods last won a major at the US Open in 2008, the landscape of the world game has changed.
While the European Tour proudly trumpets an unprecedented five successive major victories by its members, our US cousins fret that for the first time since 1994 not one of golf’s Grand Slam titles rests in American hands.
The fact that McIlroy became the eighth first-time winner in nine majors also points to the current state of flux in the professional game.
Yet by far the most impressive indicator of a brave new age in golf is the age profile of the reigning major champions. All four are in their 20s.
This has happened just once in living memory — in 2001 to be precise, when Woods, then just 25, completed his ‘Tiger Slam’ by winning that year’s US Masters.
The four current champions are: British Open — winner Louis Oosthuizen, 28, of South Africa; Germany’s US PGA hero Martin Kaymer, 26; another Springbok, Charl Schwartzel, 26, who stepped into the breach left by McIlroy’s implosion at The Masters and, Holywood’s 22-year-old US Open champion himself.
McIlroy’s win at Congressional was so comprehensive and inspired such excitement among American fans, it was reminiscent of Tiger’s victory at The Masters in 1997.
Chillingly so, one suspects, for men like Phil Mickelson, Ernie Els and other gifted players of their generation.
After toiling in Tiger’s shadow for a dozen years, they were entitled to expect more fruitful times at the majors following his decline.
Yet, if anything, their prospects of reaping a rich harvest in the autumn of their careers have receded.
The emergence last Sunday of McIlroy as a major player on the world stage nudges 40-somethings like Mickelson, Els, Retief Goosen, Angel Cabrera and Vijay Singh even deeper into the twilight zone.
Though he doesn’t turn 40 until August, Ireland’s Padraig Harrington is another multiple major-winner who must hear the clock ticking loudly every time he looks at the top of the leaderboard at golf’s Grand Slams.
Only a fool would suggest Mickelson’s days of winning majors are over. Or that Harrington’s ‘scary eyes’ will never again lock on one of those famous four trophies.
Guys like these have too much raw talent and hard-won experience to be discounted so frivolously.
If there were few green shoots of revival to be found in Harrington’s performance in a tie for 45th place at Congressional, a little confidence boost at the Scottish Open on the new links at Castle Stewart could help the Dubliner go a long way at Royal St Georges.
Yet as Mickelson discovered in McIlroy’s company during the first two rounds at the US Open, winning major titles has become infinitely harder than before.
The generation gap was pointed last Friday. As McIlroy scooted into a record halfway lead with opening rounds of 65 and 66, Mickelson lagged a dozen strokes behind.
Okay, it’s hearsay, but it was interesting nonetheless when McDowell relayed the views of Mickelson’s caddie Jim ‘Bones’ Mackay on McIlroy’s stunning performance during those first two rounds at Congressional.
Explaining on Saturday how the golf course at Congressional suited his young fellow Ulsterman and friend, Graeme McDowell revealed: “I spoke to Bones this morning and he said that Rory had pretty much hit it at every pin.
“That's not what you're supposed to do at a US Open, but the way the course has set up this week, it's allowed you to do that. Bones said Rory’s played the last few rounds out there like it's the Bob Hope Chrysler Classic. He's free swinging it and aiming at every pin like he's supposed to shoot 65.”
Was McIlroy, in those famous words once uttered by Bobby Jones about Jack Nicklaus and decades later by the Golden Bear himself about Tiger, playing a game at the US Open with which Bones and his employer were not familiar?
Whatever about golf’s golden oldies, these are difficult days for those who contest the ‘best player never to have won a major’ tag. With McIlroy now in the driving seat, the bus is pulling away ever quicker from Lee Westwood, 38, and Sergio Garcia, 31.
As US Ryder Cup captain Davis Love III eloquently explained: “I think Rory’s proved when he gets going, he’s hard to stop. And it took a big old pine tree and a house to stop him at Augusta.
“I keep saying this, if he hit the fairway on 10, I think he wins the Masters. If the ball hits the tree and spits to the right in play, he probably wins, too.
“He's an incredible talent. It's surprising that anyone would shoot scores so low and run away with the tournament, let alone a US Open, on a course like this. Yet it’s not surprising for him. That's the kind of player he is, when he gets going he's hard to stop.”
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