After the completion of Sunday's PGA Tour action, the USGA finalized the field for the 2012 U.S. Open Championship by adding four players.

Branden Grace, who was already in the field, and Spencer Levin both qualified via the top 60 in the world rankings.

Levin will start on the first tee on Thursday and will play alongside Brian Harman and Mikko Ilonen.

The USGA had left five spots open for those possibly moving into the top 60 in the world. Since just two players earned those spots, the top three alternates from sectional qualifying earned a spot at The Olympic Club next week.

Colt Knost won the 2007 U.S. Amateur at The Olympic Club, and was one of the three alternates to get into the field. Ironically, the player Knost beat in the finals at the Amateur, Michael Thompson, will be one of his playing partners for the first two rounds. They will start alongside Steve Marino off the first tee on Thursday,

The other two alternates to get in were Justin Hicks and Kyle Thompson.

Hicks is paired with Brice Garnett and Jesse Mueller, while Thompson will play the first two days with Samuel Osborne and amateur Brooks Koepka.