How Rory McIlroy Could Still Exceed His Best Ever Performance

By this time next year – and if not then by mid-season 2024 – Rory McIlroy has a chance to accomplish what in golf has been the nearly impossible: set a personal performance peak, fully retreat from it, then re-establish an even higher peak.

McIlroy established his career peak nearly a decade ago. Between 2011 and 2015, he won four Major championships and finished top 10 in four others.

It’s not that Rory McIlroy has slumped since then. Between 2016 and 2018, he completed six Major top 10s, including a tie for second at the 2018 British Open. But since 2019, an older and wiser Mcilroy has to a significant degree replicated his youthful peak.

He’s landed nine Major top 10s, and although none of those were victories they do include three top fives this year alone. He was second at the Masters, tied for fifth at the U.S. Open, and was third at St. Andrews.

The best way to measure a player’s dominance at his peak is to average the standard deviation of that player’s 10 best showings in Majors over a block of five consecutive seasons.

When you do that for Rory McIlroy between  2011 and 2015, it works out to -1.72.

In short, at his best during those peak seasons, McIlroy was nearly one and three-quarters standard deviations better than the average of his peers.

How good is that? Good enough to tie Lloyd Mangrum and Lighthorse Harry Cooper for 26th among male golfers all time for peak performance. Among all players male and female, those same three players are tied for 48th.

Here’s the thing. Once a player establishes a legitimate peak – let’s say in excess of 1 standard deviation better than his or her peers – it is virtually unprecedented for that player to retreat from that peak and then re-establish a whole new peak several years later.

In fact, only one player has ever done so. That singular exception is Jack Nicklaus. Between 1962 and 1966, Nicklaus won six Majors and produced a -2.26 peak rating that was, at the time, second only to Arnold Palmer’s -2.32 peak from 1960 to 1964.

From 1967 through 1970, Nicklaus did not exactly slump – he added two more Majors – but Nicklaus plainly retreated from his peak.

Then in 1971, Nicklaus began running off performances that created a new and even better peak.

Adding six more Major titles through 1975, he reconstituted and improved his peak to -2.35, only fractionally behind Palmer’s early 1960s peak.

Nearly a half-century later, Nicklaus remains the only player to establish a strong peak, fully retreat from it, then re-establish an even higher peak.

Rory McIlroy has a chance to join Nicklaus in that elite company if he can repeat his 2022 Major showings across the next four to six Major championships.

During the four 2022 Majors, even a winless Mcilroy still averaged a performance that was 1.75 standard deviations better than the average of his peers.

Were he to repeat in 2023 what he did in 2022, his 2019-23 peak would sit at -1.66, less than a tenth of a point below his -1.72 peak of 2011- 15.

Of course, McIlroy could do even better in 2023 than he did in 2022. He remains in his prime, being just 33 years old. And that’s where the real hope lies for Rory McIlroy to re-establish a new personal peak next year.

It wouldn’t take much. If Rory were to improve his 2022 Major showings by a mere one stroke per event, he would raise his new peak to -1.73, exceeding his 2011-15 peak, if only by a fraction.

Even then there’s no guarantee any of those performances would result in a Major title…but the odds are good they would generate one or two.

On Tour, a score that beats the field average by two standard deviations has a plausible chance to be the winning score. Under that one-stroke-improvement scenario, McIlroy would have two +2.0 or better Major performances next year.

Obviously, it would help both Rory McIlroy and his reputation to actually win a 2023 Major or two, and peak rating be damned.

But since there is no such thing as defense in golf, winning is often uncontrollable. All McIlroy — or any player — can really do is maximize their own performance.

A player’s peak rating is an excellent measure of his ability to maximize performance. Winning is a byproduct of that performance maximization.