In the 1999 drawn Munster hurling semi-final between Clare and Tipperary, David Fitzgerald gave one of the greatest goalkeeping performances of the decade. As well as an impeccable handling display, he made the save of the season from Paul Shelly before scoring the equalising goal with a penalty in stoppage time.

Fitzgerald deservedly won the man-of-the-match award but, with five minutes remaining, a Tommy Dunne ’65 landed on the roof of the net for a Tipp point. Fitzgerald privately admitted afterwards that he never saw the ball because he was looking into the sun. The sliotar grazed the crossbar. If it had ended in the net, Clare would have been beaten and the high-class quality of Fitzgerald’s contribution would have lost all its value.

Inter-county hurling goalkeeping is the most perilous position in Gaelic games and it becomes even more of a gamble at stages of the summer with the intense glare from the sun. Donal Óg Cusack had one of his biggest frights as a keeper when almost being nailed with a ball he lost during the 2002 qualifier against Limerick. Cusack has revolutionised hurling goalkeeping with supreme preparation but on certain match days the sun becomes an uncontrollable element outside of every player’s command.

He tried to reduce the risk last winter when he researched and secured a pair of Oakley Racing Jacket sunglasses, the type Edgar Davids wears to protect his eyes from glaucoma. Cusack had his eyesight measured and Oakley fitted his glasses with G30 prescription lenses designed to highlight a white ball on a green background. The glasses were fitted to his exact head measurements and Cusack trained with them on the Cork team holiday in South Africa, intending to become used to them in the summer. The only drawback was the build-up of condensation when he began sweating.

That bothered him but not enough to dissuade him. Cusack continued to train with the glasses when he returned to Cork. Then an optician in Specsavers suggested that he try the Nike Maxsight tinted soft contact lenses. They were a new product that helped eliminate image distortion and improve field of vision. Major League Baseball players had begun using them to see the ball with greater clarity and reduce sun glare. Cusack went with the lenses, though he hasn’t given up on the idea of the glasses.

“The lenses get rid of any visual noise or distraction and it makes it easier on your eyes,” he says. “You can focus better and they definitely took stress off my eyes. The fact still remains, though, that you’re going to be in trouble if you look into strong sunlight. I’m still on the lookout for something and it doesn’t bother me about wearing glasses.”

Liam Donoghue from Galway wore the Maxsight lenses last summer but Cusack opened up the issue of optic advancement in Gaelic games through his visual appearance. The Cincinnati Reds pitcher Daniel Graves says the tinted lenses make “you look kind of evil” and that “opponents might look at you like you’re possessed”. Cusack looked that at times during the summer but he was just giving himself an edge in a field that is almost completely ignored in terms of aiding sporting performance.

A year ago, the Sports Vision Association surveyed 20 apprentices at Nottingham Forest FC to see if visual and technical skills were linked. By the time Forest were made aware of the results six months later, they had released six of those 20 apprentices. All six ranked low on the visual skills chart.

Visual deficiencies can be corrected but optics is rarely part of the apparatus in the ingenious structures and framework of elite sport. Statistics show that 50% of Olympic athletes never had an eye test and 30% of athletes who reached the Olympics had eye problems. Recent studies suggest that 25% of top sportsmen and sportswomen suffer from sub-optimal vision.

Gradually, the value of optics has crept into sporting systems. In 2003, Sir Clive Woodward credited the vision coach Sherylle Calder with helping England to win the rugby World Cup. Woodward subsequently took Calder with him to work with Southampton when he transferred codes. When Woodward and Calder left the Saints, Harry Redknapp, the club’s manager at the time, said Calder “was useful for people with dodgy minces”.

Sports vision is still tiptoeing into the elite market. Manchester United now have a full-time sports vision consultant on their books, with the primary objective of improving players’ peripheral vision.

Most ball sports are about aiming and anticipation but the issue of optics in hurling is more relevant than in any other sport. The ball is smaller, the game is faster and, unlike ice hockey, there are factors associated with the sun. Blue-eyed people are more susceptible than others to glare and a person’s general rate of glare recovery is between 12 and 24 seconds. The move to more floodlit games will increase that issue. During many big hurling championship matches, players clearly often react to opposition movement and noise levels because their initial visual search for the ball has failed.

“If a player’s form has gone off a bit, he trains harder and goes to the gym more often,” says Richard Hughes, an optometrist based in Galway. “But if that player had become slightly short-sighted in his dominant eye, his ability to judge depth perception and a moving target coming at him quickly would really affect him. It would happen gradually over a year or two and his timing would go off.”