Two aspects of Tiger Woods’s victory in the 2006 British Open at Royal Liverpool Golf Club stand out. First, he used just one driver all week, preferring instead to play strategically, steering clear of pot bunkers rather than trying to bomb by them. And second, he played Royal Liverpool’s four par-5s in 14 under par, the basis for his 18-under 270.

So much is different this week, what with more rain Wednesday making it softer still — a far cry from the brown-and-fast conditions on which Woods won. But the key to the course may still lie in those four long holes.

“There are four really good opportunities to make birdies out here,” two-time major champ Rory McIlroy said. “Par 5s are going to be crucial.”

Depending on the wind, each of the par 5s could be reachable in two shots. The fifth hole, now playing 528 yards, surrendered 23 eagles in the 2006 Open. The 532-yard 10th is protected in the front by a deep bunker, but played as the second-easiest hole in 2006. And the potential for scoring down the stretch is enhanced because the 577-yard 16th was Royal Liverpool’s easiest hole eight years ago — when it yielded 27 eagles — and the finishing 18th is protected by out-of-bounds down the right side with three small bunkers to the front left of the green.

“You can open up the par 5s very easily if you can hit driver,” Englishman Ian Poulter said. “It just depends whether you’re prepared to take on gourse bushes down the left-hand side, bunkers down the right-hand side on a couple of the 5s.”

Poulter, though, showed in a practice round that driver isn’t necessary to have a shot at eagle. He hit a 3-iron off the tee and another 3-iron onto the green at No. 18, which stretches to 551 yards.

Taking the pledge

A popular pastime throughout the United Kingdom during the week of the British Open is betting on the competition, and British bookies post all sorts of odds for all manner of bets.

But the R&A, which oversees the championship, now requires players to sign a pledge — just as they do on the PGA and European Tours — that they won’t partake in what is, for the rest of the citizenry, a legal pursuit.

“This whole business of keeping sport clean in terms of betting is very high on the [International Olympic Committee’s] agenda at the moment, and something that we’re following very closely,” R&A CEO Peter Dawson said. “Because it’s just a killer to sport to think that any outcomes might have been predetermined.”. . .

Earlier this summer, the R&A announced that it would take the Open to Royal Portrush in Northern Ireland, the site of the 1951 championship, which remains the only Open held outside the main isle of Britain. With the sites accounted for the next four years — St. Andrews in 2015, followed by Royal Troon, Royal Birkdale and Carnoustie — 2019 would be the earliest the tournament could go to Portrush.

But Dawson said Wednesday that date hasn’t been determined yet because the membership of Royal Portrush will have to decide on needed infrastructure improvements before preparations can truly begin. Either way, though, the inclusion of Portrush — the home club of 2010 U.S. Open champion Graeme McDowell — won’t affect the other courses used for the Open.

“We’re not contemplating removing a golf course from the rota,” Dawson said. . . .

Mark Calcavecchia, the 1989 British Open champion, withdrew from the tournament. Officials gave no reason, but in a tweet prior to the announcement, Calcavecchia cast American Airlines in an unflattering light, suggesting his withdrawal was travel-related. He has been replaced by Canadian David Hearn.