In early 2013, Fernández-Castaño played several events on the PGA Tour, finishing third in the Arnold Palmer Invitational on a sponsor's exemption and reaching the 27th place in the Official World Golf Ranking, his best to date. He earned enough money to be eligible for Special Temporary Membership on the PGA Tour, which he accepted. This allowed him unlimited sponsor exemptions for the remainder of the 2013 season. He also finished 10th in the U.S. Open, and concluded the season with more points than the 125th PGA Tour player to earn a place as a full member for 2014. On the European Tour he won the BMW Masters and finished six times in the top-10, missing only one cut in 21 events; he ended the season ranked 7th on the Race to Dubai, his best ever performance to date.