In 2004, Ross was supposed to begin the season in the minors for Detroit. However, with Detroit desperate for bullpen help, Ross was traded to the Los Angeles Dodgers on April 1 for relief pitcher Steve Colyer. He was assigned to the AAA Las Vegas 51s of the Pacific Coast League, where he was teammates with Jayson Werth and Shane Victorino, whom he went on to face in the 2010 National League Championship Series (NLCS). Injuries marred Ross's 2004 campaign; a knee injury kept him out for two weeks early in the season, he missed time from May 26 to July 15 after smashing his hand in a car door and breaking his finger, and he broke his wrist on August 25 which ended his season. In 60 games, he batted .273 with 65 hits, 17 doubles, 14 home runs, and 49 RBI. Ross spent most of 2005 with Las Vegas. From July 26 to August 11, he hit 10 home runs and had 25 RBI in 17 games. In 115 games, he batted .267 with 105 hits, 21 doubles, 22 home runs, and 63 RBI.