"It wouldn't be widely known but I've carried two sets of irons to every tournament for five years. I choose depending on the rough that week what grooves I'm going to use."

Mark Reason talks to Padraig Harrington about the impact of the groove rule change:

Harrington says: "I've talked to pros and they don't think it will make a big difference. I see it as a massive issue.

"It wouldn't be widely known but I've carried two sets of irons to every tournament for five years. I choose depending on the rough that week what grooves I'm going to use."

In the heavy rough of the majors Harrington uses the v-grooves that will still be legal next season. They hit the ball 30 yards further out of the thick stuff than the box grooves. But at the regular events Harrington has tended to use his box grooves, because they don't produce those 'fliers' that send a ball 10 yards over the green.