How to pick an Open champion: Our formula for predicting the Claret Jug winner

The Open Championship is, fittingly. the most open of golf's four majors. The fickle nature of links courses and seaside weather typically mean the tournament's only predictable feature is its unpredictability.

But what if we could use past trends to build the model of a Champion Golfer of the Year?

It is a hard task, as previous winners at this week's venue Royal St George's attest. Little known American Ben Curtis won at odds of 500-1 in 2003 before Darren Clarke secured an emotional victory at 200-1 in 2011.

Telegraph Sport looks at experience, world ranking, current form, Open history and more to try and point us in the right direction.

Age

More so than the three majors held across the Atlantic, older players can thrive at the Open. This is because links golf puts a premium on course management and strategy, and having a memory bank of rounds played in wild conditions can help when the going gets tough. There also tends to be more roll on the fairways thanks to dryer, springier turf meaning shorter hitters can thrive.

The average age of Open winners since 2000 is 33, though five of the past nine winners were between 39 and 43 years of age. The youngest winner this century was Jordan Spieth at Royal Birkdale in 2017 aged 23, but then he was something of a phenomenon having already tucked away a Masters and a US Open.

What does it mean for this week?

Seven of the last 10 winners have been aged 32 or older, and if you fancy that trend to hold up it puts a line through some big names. Even the likes of Xander Schauffele, Tyrrell Hatton and Masters champion Hideki Matsuyama and are still in their 20s, never mind younger talents such as Viktor Hovland, Will Zalatoris, Scottie Scheffler or Scot Robert MacIntyre.

Brooks Koepka is creeping ominously into prime age at 31, but tournament favourite Jon Rahm would be a young Open winner at 26 despite his undoubted pedigree. Rory McIlroy is bang on the mark at 32.

World ranking

The only World No 1 to win the Open since 2000 is a certain Tiger Woods, with the average ranking of winners across that period 41st.

Sandwich threw up the biggest upsets in this respect, with Curtis ranked 396th when he lifted the Claret Jug in 2003 and Clarke standing at 111th. Royal St George's is not necessarily a graveyard for favourites though: world No 2 Greg Norman shot a 63 on his way to winning in 1993.

Since Clarke's victory, every winner has ranked inside the world's top 40 with the average ranking of the past seven winners just 14th.

What does it mean for this week?

Depending on your perspective, we are due an Open upset or recent history suggests we need to look for a player consistent enough to rank in the world's top 40.

Players of interest below that mark include Ian Poulter, Justin Rose, defending champion Shane Lowry, Adam Scott, Sergio Garcia and Branden Grace.

English hopefuls Lee Westwood and Paul Casey are inside the top 40 in the world though.

Open history

Nine of the last 10 Open winners had a top-10 at the tournament on their CV, which is a strong trend. Do not get too hung up on their previous performance though, with seven of the last of the last 11 winners missing the cut in their previous Open outing. No player has retained the Open since Padraig Harrington at Royal Birkdale.

Links golf is an acquired taste and having some form of past success at seaside courses is important.

What does it mean for this week?

Not helped by the one-year delay due to coronavirus, some big names such as Collin Morikawa and Hovland are making their Open debuts on the Kent coast. Power players Byrson DeChambeau and Justin Thomas have not taken well to the vagaries of links golf, with fellow countrymen Webb Simpson, Daniel Berger and Patrick Cantlay also yet to register a top 10 finish.

Justin Rose has a patchy Open record but did finish T2 at Carnoustie in 2018. Another English chance is Matt Fitzpatrick, who lost out in a play-off in Scotland last week, is without an Open top 10.

Rahm is without a top 10, but did finish T11 in 2019 at Royal Portrush when he slipped down the leaderboard on the final day with a 75. The Spaniard has also won two Irish Opens on links courses.

Leading fancies Koepka, Spieth, McIlroy, Schauffele and Dustin Johnson all meet the criteria.

Current form

The pros have contrasting philosophies when it comes to playing the week before a major, with many following Woods' example of skipping the previous event to conserve energy and practice.

However, there is some evidence that playing the week before the Open is a positive. This may be because it is preceded by the Scottish Open which in recent times has been played on links style courses. For American players making the journey, a tune up in Scotland can be just the tonic. Phil Mickelson, who for a long time struggled to make an impression at the Open, won the 2013 Scottish Open the week before winning the big one at a parched Muirfield .

Eight of the last 10 Open winners played the week before, and the same number had at least one top-15 finish in their previous three starts.

What does that mean for this week?

Koepka, Johnson and Spieth's decision not to play in Scotland raises a doubt over them, though Koepka has a history of barely featuring in regular events before hitting the top of the leaderboard in majors.

Johnson has been in poor form, without a top 10 since the Genesis Invitational in February. Other Americans with strong Open form include Rickie Fowler and Matt Kuchar, but both have been off the radar for a while.

Rose does not have a top 15 in his last three starts but Hatton does thanks to a runner-up finish at the Palmetto Championship.

Rahm, Thomas, Schauffele and McIlroy all played in Scotland with varying results, but it could hold them in good stead. DeChambeau and Reed did not play.

In the winners' circle

They say winning is a habit, and eight of the last 10 Open winners had a win under their belt earlier in the season. Lowry had won in Abu Dhabi in February 2019, Francesco Molinari at Bay Hill in the Arnold Palmer Invitational in 2018, Jordan Spieth at Pebble Beach in 2017 and Henrik Stenson at the BMW International in Germany in 2016.

So despite the Open's reputation for throwing up surprises, the winner is often a player who has already troubled the trophy engravers.

What does it mean for this year?

Johnson is without a win this year, as are perennial major bridesmaids Schauffele, Tony Finau and Louis Oosthuizen. English hopefuls Rose, Fitzpatrick and Tommy Fleetwood are also without a victory.

Paul Casey does not often get himself over the finish line, but did win the Dubai Desert Classic earlier this year.

Spieth at the Valero Texas Open, Koepka at the Phoenix Open and McIlroy at Quail Hollow have all claimed silverware in 2021, as have Rahm and DeChambeau.

So who's going to win the Open?

If you want to follow these trends to the letter then we should be able to discount the following players: Hovland and Morikawa on account of a lack of experience, DeChambeau and Thomas for a lack of solid Open form, Dustin Johnson for a shortage of current form and the likes of Rose, Schauffele and Fleetwood for not winning in 2021.

Brooks Koepka ticks most boxes: he is into his 30s, has a victory this year, two top 10s in his last three starts and has two top six finishes at the Open. He also started his professional career in Europe and has Northern Irish caddie Ricky Elliott on the bag.

The one trend that counts against him is the fact he did not play in Scotland last week, although he has a history of finding form without warning in the biggest events. Jordan Spieth is in the same boat as a former Open winner with a win this season, but did not play last week.

Of the leading contenders, all signs point towards Rory McIlroy despite his missed cut in Scotland last week. The average age of Open winners this century is 33 and McIlroy is 32. He played last week and finished T7 at the US Open three starts ago and has finished in the top five in his last four Open appearances stretching back to his win in 2014.

It takes a brave man to back Paul Casey at a major, but based on trends alone his profile appeals. He is now a seasoned links player aged 43, won in Dubai earlier this season, is ranked 21st in the world rankings, has two top 10s in his last three starts and two top 10s at the Open although his recent record is poor. The only thing missing is a start in Scotland last week.

He ticks every box but can he stand the heat of contention?

Jon Rahm is a worthy favourite, in sumptuous form with a US Open on his mantelpiece. Open finishes of T59-T44-MC-T11 suggest he has struggled to stay patient and a slightly madcap layout at St George's could test his temper. He is a more mature player these days, though.