Vision on

Now fast-forward 12 months. Winnings of ?329,390 (287,769) had Karlsson a lowly 98th on the money list. He and Stenson failed to retain the World Cup (although they were named "team of the year" in their homeland). And he failed to add to his six career victories. Not too good.

Ah, but there is a good reason for the two-time Ryder Cup player's slide into apparent mediocrity. In May last year he left the Tour, complaining that he could no longer see the ball properly, fluid behind the retina of his left eye causing depth perception problems that made golf at professional level impossible. Even at the Scandinavian Masters last July, where he played in the pro-am to gauge any improvement, he was reduced to looking from the side to see what kind of lie he had. Looking straight down at the ball he had no idea if it was sitting up or down.

"My vision was like when you come up from being underwater – all fuzzy," reveals Karlsson, who stands 6'5" tall. "I was told it was stress-related. But I think that is a medical term for 'we don't really know'. People who travel a lot are susceptible to it, as are those in stressful jobs. A lot of doctors and athletes and pilots suffer from it.

"I have to say I didn't feel stressed when I was diagnosed. But my life was a bit intense. I was playing well and had been travelling a lot. It cannot be good for the body to sit in aeroplanes as much as I do.

"It wasn't an ideal time, but it would have been even worse if I had had to make ?300,000 to keep my card. I'm in a privileged position in that I am exempt on Tour for a few years. But it did stop me building on the success of 2008. I ended up missing three majors, which was unfortunate."

It would be November before Karlsson returned to the Tour and he has made steady progress since. In December he lost to Edoardo Molinari of Italy in a play-off for the Dunlop Phoenix title in Japan. And last week, of course, he cruised to victory at the Qatar Masters with a bogey-free final round of 65 that left high-profile rivals like Lee Westwood and Paul Casey gasping in his wake. Clearly, he is edging closer to the form that brought so much success in '08.

"I'm fine now," he insists. "I had the last check-up on 22 December. There was a little bit of fluid left but it was no more than had been there before last May. I have to keep monitoring it every couple of months from now on, but so far it feels good.

"As for my golf, if 2008 is ten out of ten, I'm about a seven right now. But I'm getting better quite quickly. I had a few bad habits when I did come back and I was weak. I hadn't been able to do any strength training, or anything that would send my pulse over 120. All I could really do was take long walks and stretch. That was it."

Looking ahead, Karlsson, not normally one to set too many goals in a sport he long ago recognised as less than predictable, is nevertheless keen to make what would be a third Ryder Cup appearance this October at Celtic Manor.

"If, like me, you have played in a couple of Ryder Cups, you want to get back there," he smiles. "It's a fantastic experience. But, at the same time, it is important for me not to put too much pressure on myself. So I'm trying to put it aside. Even if I never play again, I've been part of two great matches.

"If I get close to qualifying, I like to think I'd be a strong candidate for a pick, but that depends a great deal on who is in and who is out. Whatever happens, this is going to be the strongest European team ever. Look at the world rankings; there are seven Europeans in the top-11. I was talking to some of the caddies yesterday. They reckoned that there are 17 players who cannot miss! That's not good for a 12-man team, even before you count the usual couple of surprises."

One thing that has changed for Karlsson and the rest of his fellow players this year is the grooves in their clubs. Gone are the so-called "square" grooves (except for the controversial use of pre-1990 Ping Eye-2 wedges by Phil Mickelson and others) that produced so much easy spin for the accomplished player even from heavy rough, replaced by "v" grooves designed to make sure that balls run out more on landing. While this has been largely welcomed by those fed up watching the pros casually spinning pitches from long grass that ought to make such shots a lot more difficult, the thoughtful Karlsson has an alternative view of the changes.

"I do wonder why they have altered the grooves rule," he says. "The game is not about we professionals; it is about the amateurs. There would not be professional tours if not for the fact that the amateurs like to watch us. So I would never have done anything to make the game harder for them (the rule change kicks in for the rest of us in ten years' time).

"The amateur who struggles all day gets a lot of pleasure from the bunker shot or pitch that happens to spin correctly. That is fun for them. But a decade from now those shots will be all but impossible. Even in a couple of years they will be much more difficult. No one is making clubs with the old grooves so they will be harder to find."

Unusually for a leading professional – a generally self-absorbed bunch – Karlsson also has an alternative strategy for golf's rules-makers.

"Why do they not introduce a bigger golf ball for everyone?" he asks. "They are easier to hit. And you don't need perfect fairways because the ball will sit up more. Maybe the hole would have to get slightly bigger. But that is OK. That would all make the game easier for the amateurs.

"I played with (R&A chief executive] Peter Dawson a couple of years ago at the Dunhill Links and told him he should be making things easier for the amateurs and harder for us. Golf is about amateurs and not about the professionals. And anything that increases the gap between the two groups cannot be good."

Good grief; a wealthy pro golfer with a genuine conscience. Root for the big man whenever you can. He is one of a dying breed.