Pay no attention to what Rory McIlroy shoots in the first round of the British Open on Thursday, because it hardly matters. McIlroy has opened so many tournaments in spectacular fashion this year — a 63 at the Memorial, a 63 in Dubai, a 64 last week at the Scottish Open — that it is almost expected.

When he plays well in the second round, that will be news.

“It’s just got into my head,” McIlroy said Tuesday.

How could it not? McIlroy’s cumulative first-round score in 13 stroke-play events this year is 44 under par. He has broken par 11 times, and his worst performance was a 3-over 74 at the Irish Open.

McIlroy’s cumulative score in his 13 second rounds: 9 over, with some scores that don’t resemble those from a player of his caliber. There have, too, been massive swings. His opening 63 at the Memorial was followed by an inexplicable 78 the very next day on the very same course. Last week at the Scottish Open, he countered his first-round 64 with a second-round 78, going from 7 under after day one to even for the tournament.

What gives?

“I may be putting a bit too much pressure on myself going out on Fridays and trying to back up a score,” said McIlroy, a two-time major champion and former world No. 1 who has fallen to eighth in the rankings. “I have no problem shooting a low one on Thursday. There should be no reason I have any problem shooting a low one on Friday.”

This tendency isn’t wholly new for McIlroy. At the 2010 British Open at St. Andrews, he opened with a 63 and followed it with a ghastly 80. He finished tied for third, his only top-20 finish in six British Open appearances.

A chance to take advantage: There is a secret to Hoylake — it is the only links course in the British Open rotation with four par 5s. When Tiger Woods won at this course, he played them in 13 under.

“I think that’s the one thing we’re all looking at — if we can take advantage of the par 5s,” Adam Scott said Tuesday. “There’s a real opportunity for a low score out there with some good golf on the other 14 holes. And it’s going to be a big part of the strategy of how we’re playing.”

The fifth hole played into the wind Tuesday at 528 yards. Woods hit driver — yes, driver — and a fairway metal into the front bunker. Hunter Mahan reached in two. The 10th hole (532 yards) was played with a right-to-left wind, while the 16th (577 yards) and the 18th (551 yards) were downwind.

About that putter: Adam Scott, along with Keegan Bradley the only players to win a major with a long putter, has said he won't change until the new rule against the club goes into effect, and is not about to do it sooner.

“I haven’t messed with it at all,” Scott said. “I thought I’d worry about that when I have to change.”

Who's No. 1?: Scott went to No. 1 in the world in May, and then won his next tournament at Colonial. He has been atop the world ranking for two months, though that position is up for grabs at a major.

Early projections suggest that Henrik Stenson, Justin Rose, Bubba Watson and Jason Day have a mathematical chance to reach No. 1 by winning the British Open. Day at No. 6 would have a chance over Matt Kuchar at No. 5 because the Australian has been injured, and so his tournament divisor is lower.