Jon Rahm
Putter Changes:
What The Numbers Say
Three putters. One season. Clear timestamps on each switch. We used DataGolf Strokes Gained: Putting data to track what actually happened — round by round.
Traditional stats like putts per round or greens in regulation tell you what happened. Strokes Gained tells you how much it mattered relative to the field.
The concept, developed by Columbia professor Mark Broadie, compares every shot against the statistical average outcome for all Tour players from that same position. Make a putt from 15 feet when the field averages 1.7 putts from there, and you’ve gained 0.7 strokes. Miss it and you’ve lost 0.3. Every shot on every hole, across every round, summed into a single number.
How many strokes per round a player gains or loses on the greens versus Tour average. The core metric throughout this series. Positive = better than field. Negative = worse.
Measures how much closer to the hole a player leaves their approach shots versus Tour average from the same distance and lie. The strongest single predictor of Tour earnings we’ve found.
Captures chipping, pitching, bunker play — any shot within 30 yards that isn’t a putt. Separates short-game skill from putting, which traditional stats bundle together.
The sum of all four SG categories: off the tee, approach, around the green, and putting. A positive total means the player performed better than the average Tour player across their whole game.
The short version: Strokes Gained is context-aware. Putts per round isn’t — it treats a 3-foot tap-in the same as a 40-foot lag putt. SG accounts for the difficulty of every shot, which is why it’s a far more honest measure of whether a putter change actually worked.
Golf is a noisy sport. A single round of SG: Putting can swing from −3 to +3 based on hole locations, green speeds, and variance that has nothing to do with how well someone is putting. One hot round tells you very little on its own.
A rolling average smooths that noise by averaging across a moving window of recent rounds or tournaments. The red line in the chart uses a 5-round window — each point represents the average of that round plus the four before it. This reveals the trend rather than the fluctuation.
Can be misleading. Rahm’s +2.44 with the #7S at Riviera looks significant on its own — but a single data point in a noisy sport is rarely the signal it appears to be.
Filters out most of the variance. When the rolling average sustains a shift upward over several weeks, that’s a more reliable indicator that something genuinely changed.
A genuine putter change effect should show the rolling average breaking out of its previous range and staying there — not spiking once and reverting. That’s the test we’re applying throughout this series.
Rolling averages don’t prove causation. The putter might have changed at the same time as form improved for other reasons — course conditions, mental state, swing changes. The data describes what happened, not necessarily why.
When Rahm moved to Callaway in 2021, the Odyssey 2-Ball Ten came with the deal. It lasted roughly half the season before the White Hot OG Rossie S replaced it at the Memorial. The Rossie became his gamer through 2022.
At Riviera for the Genesis Invitational, nothing was working — rounds of −3, −0.15, and −1.88 SG: Putting before the switch. So for round 4, Rahm reached into the bag and pulled out an OG #7S he’d been testing in practice. Mid-tournament. Three poor rounds already on the card.
Each dot = one round, coloured by putter era. Red line = 5-round rolling average. Outlined dots = notable moments. Hover for round details. Click legend to filter eras.
The immediate result was striking: +2.44 SG: Putting in that round alone — about two strokes better than his rolling average to that point. The #7S stayed in the bag one more week, then the Rossie came back.
The rolling average in the chart tells the fuller story. The Rossie was already working before the #7S experiment — the 5-round average had been climbing through the latter part of 2021. The brief switch produced one exceptional round, then the average settled back to where it had been building to anyway. Whether the #7S caused the spike or Rahm was simply due a strong round on any putter is a question the data can’t answer.
What it can show: the season finished with three wins — Open de España, the Columbus event, DP World Tour Championship — all with the Rossie, backed by some of the most consistent putting numbers in the dataset. The story of 2022 is a Rossie story. The #7S is a footnote that happened to produce one memorable round.
The Verdict
The Rossie was a genuine improvement on the 2-Ball Ten. The #7S experiment delivered one exceptional round and then normalised back to baseline. The data backs a nuanced reading — not the clean equipment story the headlines suggested. Knowing the difference is what The Search is really about.
- 01 — Jon RahmYou are here
- 02 — Collin MorikawaFour putters, same ceiling →
- 03 — Justin ThomasChanged putter at a Major. Then won it. →
- 04 — Rickie FowlerEight years. Six putters. One comeback. →
