US Open 2021: Your major championship form guide ahead of this week's tournament in San Diego

'Normal service' resumed last month at Kiawah Island where Phil Mickelson made it 12 wins out of 13 for American golfers in US majors.

Hideki Matsuyama had managed to interrupt the sequence at Augusta National in April, when he became the first Japanese male to win any of golf's four major championships.

But 50-year-old Leftie maintained recent American dominance on home soil by claiming his sixth major title in a little over 17 years.

You have to go back to Pinehurst in 2014 (and Germany's Martin Kaymer) to find the last time a non-American won the US Open.

Latest odds for this week's US Open

And the stats regarding this current trend are quite stark. This is how they breakdown over four-year segments since January 1st, 1998.

Non-American Champions in US Majors (1998-2021)

2018-21: 1/11 (9.1%)
2014-17: 5/12 (41.7%)
2010-13: 7/12 (58.3%)
2006-09: 6/12 (50.0%)
2002-05: 4/12 (33.3%)
1998-01: 4/12 (33.3%)

Top-3 Finishes By Non-Americans in US Majors (1998-2021)

2018-21: 11/40 (27.5%)
2014-17: 18/39 (46.2%)
2010-13: 29/46 (63.0%)
2006-09: 20/47 (42.6%)
2002-05: 17/40 (42.5%)
1998-01: 12/39 (30.8%)

So who are the leading American pros heading to Torrey Pines this week, and who are the main overseas challengers?

Eight home pros

Bryson DeChambeau: The defending champ who won at Bay Hill in March, and followed this with a podium finish in The Players Championship.

Tony Finau: Has a great record at Torrey Pines and has accumulated 10 T-10s in majors - nine of these since the beginning of 2018. One of these days...

Dustin Johnson: Still world No 1 and on Sunday posted his first T-10 since February, which is an encouraging sign following missed cuts in the opening two majors of 2021.

Brooks Koepka: Pre-major form is becoming irrelevant for Koepka who rarely struggles in the 'Big Four'. His last 14 majors have yielded four wins, three runners-up, and three other top-10s.

Phil Mickelson: You have to feel a tad sorry for Leftie. For decades he has desperately been attempting to win the second major championship of the calendar year. And when he finally achieved this last month, he discovers it's no longer the treasured US Open but the PGA Championship instead. Surely lightning won't strike twice in 2021.

Collin Morikawa: Last year's PGA Championship winner and current world No 4. The 24-year-old, who resides in Las Vegas, is developing into one of the most consistent pros in world golf.

Patrick Reed: Despite being a leading golfer since 2014, he didn't register a major championship top-10 until the PGA Championship of 2017. Since then, and largely thanks to his Masters' victory the following April, his form in the 'Big Four' has improved dramatically. Winner at Torrey earlier this year.

Xander Schauffele: Born in San Diego and tied-second at Torrey Pines in January. Usually plays well in the majors, and his missed cut at last month's PGA Championship can simply be put down as being a hangover from Augusta National where his six strokes at the par-three 16th ruined his chances of overhauling eventual champion Matsuyama. Seven top-six finishes in the majors since the start of 2017.

Latest odds for a top-10 finish at this week's US Open

Seven overseas challengers

Abraham Ancer: A tidy golfer who usually looks solid from tee-to-green, therefore traditionally the sort of player who should do well on US Open courses. Tied-eighth at Kiawah Island last month.

Tyrrell Hatton: Despite being the world No 9, still tends to walk under the radar a little. He finished in a tie-for-second on Sunday after playing the final 54 holes better than anyone else in the field.

Rory McIlroy: Can never be ruled out despite recent mediocre form in the majors - by his high standards. Yet he proved last month that he still possesses all the necessary tools to perform well on tough courses - as his victory at Quail Hollow illustrated.

Hideki Matsuyama: Must still be full of confidence following his momentous victory at Augusta. He contended for 46 holes at the PGA Championship last month, having trailed by just two strokes at the half-way stage. However, he then covered the final eight holes of his third round in six-over-par.

Louis Oosthuizen: The 2010 Open champion from St Andrews surely deserves another major title. There have been six other top-three finishes in the majors, five of these on US soil.

Jon Rahm: After his positive test for Covid meant he was unable to tee-off in the final round at Muirfield Village earlier this month - despite holding a six-stroke lead thru 54 holes - many will be hoping the Spaniard will secure his maiden major title in California. Is a former winner at Torrey Pines.

Justin Rose: Perhaps not a winner this week, but his excellent consistency in the majors makes him a strong each-way option. A former winner at Torrey.

Twitter: Andy Swales@GolfStatsAlive

MC* - Missed Additional 54-Hole Cut

Key: P (PGA); M (Masters); U (US Open); B (The (British) Open