This month HNA take a look at nine-hole scores and the changes that will be introduced on 1 October as part of the transition to the World Handicap System.
Nine-hole competitions and nine-hole rounds are becoming increasingly popular globally. This is mainly due to the time it takes to play 18 holes, but also due to personal preferences. As such, nine-hole scores are an important part of the handicap calculation.
We are sure you have noticed that, at many courses, one nine plays harder than the other nine. To ensure that the Handicap Indexes are as close as possible to the golfer’s ability, we will be introducing nine-hole Course Handicaps and a revised nine-hole handicap score calculation on the 1st October 2019. This will be in line with that required under the World Handicap System Rules coming in January 2020.
What you need to do when playing nine holes:
From the 1 October, simply look up your 9-hole Course Handicap, which is what you will play off for the nine you elect to play. When entering your score, use your 9-hole Course Handicap to adjust your maximum score on any hole that you blow out on and enter this Adjusted Gross Score for nine holes – the system will do the rest.
The current 9-hole system:
Our current 9-hole handicap calculation takes the nine-hole Adjusted Gross Score you enter and the Slope of the tee you played off, and then adds par for the second nine, plus half your handicap strokes, resulting in an 18-hole Adjusted Gross score.
The actual calculation is as follows:
9-Hole Score Differential = (Adjusted Gross Score for 9 holes x 113/Slope Rating + second nine par + 0.5 x Course Handicap) – Course Rating.
Future World Handicap System:
When all the courses in South Africa were rated with the USGA Course Rating System, a Course and Slope Rating for each nine, as well as for the overall course, was determined and is currently published on the HNA website. As of October, we will now use these 9-hole ratings to determine your nine-hole Course Handicap.
Example:
On some courses, although par is the same on each nine, the Course Rating and Slope can be very different. For example, if we look at Randpark Firethorn, the par-72 course where the 2019 SA Open was played, we can see that the White course for Men has a CR/SR of 36.0/132 for the front 9 and 37.7/139 for the back nine, with an overall rating of 73.8/136. So the 18-hole Course Rating is 73.8/136, but it is different by 1.7 shots on each nine and the Slope rating varies by 7.
Therefore, if a golfer at Randpark always plays the harder nine, with a CR of 37.7/139, under our existing system of just using the 18-hole Course Rating, they would have a Handicap Index higher than it should be.
From October 2019, if you are going to play nine holes you will first need to look up your nine-hole Course Handicap, in the same way that you currently look up your 18-hole Course Handicap. You will able to do this on the HNA phone app, handicap terminal or from the Club System or a Course Handicap Chart at the course.
This 9-hole Course Handicap will then be used by you to enter your Adjusted Gross Score for the nine holes (adjusted for the maximum score allowed on any hole). When you then enter this 9-hole Adjusted Gross Score into the handicap system, it will automatically be converted in to an 18-hole differential on your handicap score history by adding par plus your remaining handicap strokes for the second nine, plus 1 extra shot.
9-hole differential = ((9 Hole Adjusted Gross Score – 9 hole CR) x 113/9-hole Slope rating)
So, the full formula to convert your 9-hole score into an 18-hole differential will be:
((Adjusted Gross Score – 9-hole CR) x 113/9-hole SR)
+
((2nd Nine Par + Player’s 2nd Nine CH Strokes + 1) – 2nd Nine CR))
Please note that if you don’t want to adjust your scores or you are not sure about what to enter for your handicap score, you can enter your hole-by-hole scores on the app, terminal, or HNA website. The system will then adjust your scores for the maximum allowed on a hole, according to your Course Handicap, and enter your Adjusted Gross Score for you.
This 9-hole change, along with all the other changes to be introduced, will be further covered closer to the time, and the revised Handicap Rules will also be circulated prior to the implementation date.
