Troncoso split the 2007 season between the Single-A Inland Empire 66ers of San Bernardino and the Double-A Jacksonville Suns. He was added to the Dodgers 40-man roster after the '07 season, and made his Major League Debut on April 1, 2008, for the Dodgers against the San Francisco Giants. He pitched to one batter and induced an inning-ending double-play. He split the season between the Triple-A Las Vegas 51s and the Dodgers. He finished the 2008 season with a record of 1-1 and a 4.26 ERA in 32 relief appearances for the Dodgers.