PGA Championship preview: Clippd’s Digital Twin vs Oak Hill’s ‘Plateau’

Words by
Dr Chris Robertson, Head of Data Science at Clippd
PGA Championship preview: Clippd’s Digital Twin vs Oak Hill’s ‘Plateau’

Stepping onto the 15th tee of the East Course at Oak Hill, venue for this year’s PGA Championship, will be a moment of reckoning, not least for those with designs on lifting the Wanamaker Trophy. At 155 yards, this short par-3 is an homage to the Postage Stamp at Royal Troon, with its long, thin, elevated green surrounded by trouble on all sides. To conquer it will require a fine touch and considerable levels of intestinal fortitude.

Hole 15, 'Plateau:' Image: Golf Digest's 'Every hole at Oak Hill' video

“Hitting the target is an absolute must,” states Garrett Morrison on The Fried Egg’s excellent podcast about the changes to the East Course at Oak Hill Country Club. Much has been said and written about the work done on a course that has staged three previous US Opens, three PGAs, a Ryder Cup and US Amateur Championships. Consulting architect Andrew Green’s “historical renovation” of the East Course is sympathetic to the original 1925 design of Donald Ross. Green has removed many trees, reconnected with Ross’s “wild green shapes” and added bunkering that he describes as “bold and aggressive”.

The old par-3 15th with the pond put in by Tom Fazio (Google Earth)

‘Plateau’, the par-3 15th, is one of the most eye-catching changes. The hole comes in the middle of a fine closing stretch, and straight after the drivable par-4 14th. Players will be confronted with a glimmering mirage of green amid potential carnage. The pond that Tom and George Fazio introduced to the right of the green in the 1970s has been removed and replaced with a closely mown run-off area. Anything leaking right will need to be rescued with an expertly played chip shot over a high lip to a narrow target.

The slope at the back is severe, as are the contours running through the green

The two spectacle bunkers at the front and the one running down the left side, are new. They're deep and set into lower slopes of the turret on which the green is perched. The slope at the back is severe, as are the contours running through the green, not least the spine that runs through the middle. 

The Clippd data science team selected four likely pin positions and used Clippd’s “Digital Twin” technology to define the best play for each. Aim for the middle of the green and get out with a par? Or take dead aim and give yourself the best chance of a major-clinching birdie? 

Methodology: Digital Twin

In the absence of professional shot data on this redesigned hole, "Digital Twin" provides the insight required. This technology allows us to simulate millions of on-course shots, played by a digital version of the average Tour pro. 

Several factors are built into these simulations, including green firmness, rough height, elevation change, weather conditions, the presence of hazards around the green/flag and even the extent to which a player is short-sided. For the purposes of this analysis we have assumed fairly neutral weather conditions with little wind and no rain, that the greens will be playing firm and fast and the rough deep (approx. 4 inches).

We can harness the inherent randomness associated with the outcome of individual shots

So, conservative or aggressive? To answer the question we then simply simulate (on the order of 10k times) this average tour pro playing the hole in two parallel scenarios, one in which he fires straight at the pin and the other where he takes the “safe” option and hits to the middle of the green. By aggregating such a large volume of simulations we can harness the inherent randomness associated with the outcome of individual shots and estimate the likelihood of particular events such as the probability of birdie/bogey.

Graphics by Matt Miller

Verdict: Aggression pays

It’s clear from the graphics above that the conservative play is not the best strategy for the 15th on Oak Hill’s East Course. Even though the expected green in regulation percentage is approximately 16% higher than the aggressive strategy on average (66% versus 50%), a player executing to perfection is still left with a putt of approximately 40 ft to any of the four pins. 

It makes a two-putt par anything but a forgone conclusion. In fact, the average three-putt percentage from this distance on the PGA Tour in the last two years is approximately 10%, and this doesn’t even account for the added difficulty of navigating the ridge in the middle of the green. 

In general, given the distance of the hole (ranging between approximately 140 and 165 yards) and the accuracy of tour pros from this distance (average proximity on the PGA Tour over the last two years is approximately 25 ft), it makes sense that a more aggressive strategy would be the better option. Indeed, even for the most treacherous pin (the front left pin plays at least 0.04 shots harder than the others according to our analysis) the expected GIR% is still around 47%.

The price of a miss

While the aggressive approach does result in a slightly lower bogey probability across the board it does bring the bunkers and run off areas more into play. To demonstrate the potential impact of some of these misses, a pair of examples are shown for each pin along with the chance of bogey should a player misplay their approach and end up there. 

The impact of the new run-off area

Out of all of these the most penal miss is down the bank long of the green but significant challenges await any player finding the run off area for pins on the right of the green. The steep elevation change, firm greens and lack of green to work with results in an increase in bogey or worse probability of approximately 11% than what might be expected from a “typical” shot from this distance and lie. 

A view of the green from the new run-off area to the right of the green

Again, the models that estimate the difficulty of each of these shots account for green firmness, rough height, elevation change, weather conditions, the presence of hazards around the green/flag and the extent to which a player is short-sided.

Is there a better strategy?

The analysis presented above begs the question: “Is firing directly at the pin the best option on this hole?” Or is there a “best of both worlds” approach that balances the higher GIR% and safety of finding the putting surface of the conservative play while still giving players a good look at birdie? 

By extending the application of our Digital Twin technology to take advantage of optimisation techniques we can answer this question directly. In essence, by getting the Digital Twin to play the hole many more times while providing it with an objective (e.g. minimise average score or minimise bogey or worse probability) and the flexibility to choose its own aim point, we can get it to find the best solution (i.e. our optimal aim point for each pin). 

In doing so we are able to define optimal strategy for any player on any course in any conditions. 

Front left: What's the play?

In this case, we chose to minimise average score which resulted in an optimal aim point 9 ft right and 7 ft long of the front left pin. As you might expect, this aim point increases expected GIR percentage (58%) while maintaining a similar birdie opportunity (12%). 

So, that's the play. Now it’s just a case of standing up and executing. Under pressure.