The U.S. Open began under partly cloudy skies on Thursday at challenging Oakmont Country Club where Bryson DeChambeau hopes to make a fast start to his title defence while tournament favourite Scottie Scheffler was hours from teeing off.

Even world No. 1 Scottie Scheffler knows he'll be at the mercy of Oakmont Country Club at the U.S. Open, a course he called "probably the hardest golf course that we'll play."

Top-ranked Scottie Scheffler tries to become the first back-to-back major winner in a decade by taking this week's 125th US Open, which tees off Thursday at intimidating Oakmont.The 31-year-old American is trying to become only the eighth back-to-back US Open winner,

Seventy-two holes of struggle await the eventual 2025 U.S. Open winner as Oakmont Country Club is prepared to bare its teeth for a 156-man field all seeking to claim the national championship. The par-70 course is hosting the USGA's signature tournament and the third major championship of the season for a record 10th time with golfers attempting to transverse its difficult landscape for the first time in nine years.