Rickie Fowler and Xander Schauffele made US Open history about 30 minutes apart at Los Angeles Country Club.
The pair of American golfers became the first players to shoot 62 at the US Open, and they tied Branden Grace for the lowest single-round score in major history.
Fowler and Schauffele's low rounds set the tone for a great day for scoring across the first-time major venue.
Rory McIlroy and Dustin Johnson were among the golfers that came up just short of the two leaders.
The abundance of low scores is not typical for a US Open, which was won by a six-under overall score in each of the last three years.