Unless they can find a loophole. And John Daly has found one.
At the 2010 Sony Open, Daly is playing with a 1986 set of Ping Eye 2 wedges. Another player, Dean Wilson, is also using Ping Eye 2 wedges from the late 1980s. Both players are doing so despite the fact that the old Ping Eye 2 wedges sport square grooves, the kind of grooves that are now non-conforming under the USGA's new groove rules that are in effect on the PGA Tour.
So how are Daly, et.al., getting away with it? The reasons seem pretty arcane now, but date back to what was a major brouhaha in the golf world in the late 1980s and early 1990s.
In the early 1980s, the USGA first ruled square grooves conforming. Ping introduced square grooves to the marketplace with the Ping Eye 2 irons in 1984. In 1985, Ping founder Karsten Solheim made a tiny adjustment to the shape of his square grooves (very slightly rounding the edges). With that adjustment, Solheim unwittingly sent the irons out of conformity with USGA regulations.
Or did he? The conformity or non-conformity of those new Ping Eye 2 irons and wedges in 1985 hung on interpretations of USGA regulations over the spacing between grooves on the clubface. Solheim and the USGA disagreed over the proper way to measure groove width and spacing. Solheim, measuring one way, felt his irons still conformed; the USGA, measuring a different way, disagreed.
While that was going on behind the scenes, Ping tour staff members were winning. Bob Tway and Mark Calcavecchia won majors. Strangely, no other major manufacturers jumped on the square grooves train. Today, every other club company would have clubs on the market in no time sporting the latest innovation. In the late 1980s, only Ping was making square grooves.
Then the PGA Tour got involved. The PGA Tour ruled that starting with the 1990 season, square grooves would be illegal for play in PGA Tour events. Remember, the USGA at this point says square grooves are legal. So the PGA Tour is in effect trumping the USGA's ruling with one of its own.
So Ping is faced with the technical dispute over groove measurement with the USGA, and then the PGA Tour just bans square grooves outright. Ping went to court, suing both the USGA and the PGA Tour.
Ping and the USGA reached a settlement fairly quickly. The USGA developed a new point-by-point procedure for measuring groove width and spacing; the USGA agreed to grandfather in the Ping Eye 2 irons and wedges made from 1985-89, allowing them to continue being used; and Ping agreed to make all its irons and wedges conform to the new measuring procedure going forward.
The PGA Tour, however, fought on until 1993, when it finally agreed to an out-of-court settlement with Ping. In that settlement, the PGA Tour essentially just agreed to agree with Ping's 1990 settlement with the USGA. The Tour would allow square grooves going forward, and, like the USGA, grandfathered in those 1985-89 Ping Eye 2 clubs, allowing them to continue being used in Tour events.
So here we are in 2010, and the USGA has initiated new groove rules banning square grooves, and the PGA Tour has adopted a condition of competition enforcing the USGA ruling on the PGA Tour. But the details of those 1990 and 1993 legal settlements remain in place - meaning that Ping Eye 2 irons and wedges made between 1985 and 1989 are still permissable in USGA and PGA Tour competitions, despite the new groove rules.
And that's what John Daly and Dean Wilson know, and why they are using Ping Eye 2 wedges more than 20 years old this week at the Sony Open.
But there are some catches for Daly, Wilson, and any other golfers who might want to exploit this loophole. For example: Ping Eye 2 clubs from that era whose grooves are still sharp enough for a PGA Tour player's liking aren't that easy to find (especially if Tour players start hoarding them). And Ping can't make any more of them, although it is allowed to adjust lie angles, loft angles and make shaft repairs.
Daly told the Associated Press that he expects more Tour players to try tracking down old Ping wedges. "I know a lot of guys are buying them off eBay," he said.
I'm skeptical that we'll see many more players using 20-year-old wedges, however. Most players switched to clubs that conform to the new groove rules months ago; some even earlier (Tiger Woods' clubs conformed to the new groove rules throughout 2009).
It should also be noted that no golfers outside the USGA's jurisdiction can take advantage of this loophole; the R&A was not a party to those 1990s settlements, and the old Ping Eye 2 irons and wedges are non-conforming in competitions played under the auspices of the R&A.