Revved-up Rory McIlroy has little to be angry about at BMW PGA Championship at Wentworth
If golf can drive Rory McIlroy - the world No 1 who just happens to have won twice in the past three weeks - to the brink of fury, then imagine what it must do to his rivals.
Or then, perhaps the Ulsterman's frustration yesterday was a simple gauge of the height of his standards nowadays.
His 71 in the first round of the BMW PGA Championship was his 20th consecutive strokeplay round at par or better and when one puts together staggering streaks like that, the ambition must tend to zoom skywards.
McIlroy believes it is all to do with tiredness as he is playing his fourth event in a five-week transatlantic run.
The 26-year-old threw a club in disgust on the par-five 17th, and although it was hardly the three-iron he hurled deep into the lake at Doral at March, it showed his frayed state of mind.
He came into the week having played 265 holes in three weeks. That is a lot of golf, particularly when you have been in contention for most of those holes, and those holes have been on opposite coasts in the US and the south of England.
But, fit as McIlroy is, it is fatigue between the ears that is affecting him.
"Physically, I'm all right," the defending champion said. "I got back to the room at 4.30pm yesterday and didn't leave until 6.30am, so that's 14 hours of rest right there. But mentally I can feel myself getting angry out there, which I haven't been doing the last few weeks."
McIlroy was asked if he needed to go on an anger management course, which seemed a little severe.
"No, I just need to stay in control of my emotions, because if I'm a little tired I get down on myself," he said. "But now when I look at the leaderboard, I see that one under isn't that bad. If that's the worst score of the week, I'll be doing okay."
Indeed, McIlroy is in the top 25, on the same mark as the world No 6 Justin Rose, six behind the pacesetter Francesco Molinari.
The Italian's flawless 65 was further evidence that he likes the West Course. He has finished in the top 10 for the past three years and is plainly too good to be 66th in the world rankings.
Despite only receiving an invite on Monday, Peter Lawrie leads the Irish challenge on three under which could have been far better but for a double bogey on the par four third. Damien McGrane is one shot further back while Niall Kearney is on even par.
There are a clutch of Irish on two over who will need good rounds today in order to make the cut with Darren Clarke, Graeme McDowell and Shane Lowry all struggling to find their rhythm. Michael Hoey is one shot further behind.
On five under is the Swede Robert Karlsson and one shot further behind, in a group including Miguel Angel Jimenez and Scotland's Marc Warren, is Chris Wood. The 27-year-old from Bristol is another on his way back, as surely signified by his 68.
Wood, who showed his potential with top-five finishes in his first two Open Championships, has endured a torrid spell with injury.
After finally recovering from a long-term back complaint, he fell over while having a tennis lesson last October.
The initial diagnosis was a badly bruised wrist and a month's absence. But when the pain refused to subside another scan revealed a fracture and he spent a total of five months on the sidelines.
"It was a nightmare, mainly how to fill your days," Wood said.
"There's only so much old Top Gear repeats on that Dave channel you can watch. I've fallen to 192nd in the rankings and have to climb the mountain again.
"This week and next week's Irish Open are a chance to make some progress and this will give me confidence."