May 24, 2012, Haren recorded a career-high 14 strikeouts in a complete-game shutout against the Seattle Mariners in Seattle, allowing four hits in a 3–0 victory. On November 2, 2012, after an attempt to trade him to the Chicago Cubs for Carlos Mármol fell through, the Angels declined Haren's $15.5 million option, instead buying it out for $3.5 million, and he became a free agent. Washington Nationals Haren signed a one-year, $13 million contract with the Washington Nationals on December 7, 2012. After his June 22, 2013, start against the Colorado Rockies, Haren owned a major league-worst 6.15 ERA amongst qualified starters. He had also given up a league-leading number of home runs with 19 home runs surrendered through 15 starts. Haren was placed on the 15-day disabled list on June 25 with right shoulder inflammation. He later explained that the disabled list stint was more for "mental reasons than physical reasons," as he was lonely with his family remaining in California. Haren finished the 2013 season 10-14 with a 4.67 ERA. After starting the season with a 4-11 record and a 5.79 ERA in his first 18 games, he finished the season with a 6-3 record and a 3.14 ERA in his final 13 games. Los Angeles Dodgers On November 25, 2013, Haren signed to a one-year, $10 million deal with the Los Angeles Dodgers. The deal included a vesting option for 2015, which became a player option when he pitched 180 innings in 2014. Haren started the season strong, winning five of his first six decisions. However, around the all-star break he had a brief stretch where he pitched poorly, losing five straight starts from July 5 to August 1. He turned it around again and pitched well down the stretch. He finished with a record of 13–11 and an ERA of 4.02 in 32 starts for the Dodgers in 2014. For the year, he finished second in the league in home runs allowed with 27. After the season, Haren exercised his player option for the 2015 season. Regarding rumors that the Dodgers might trade him, Haren said he only wanted to pitch in Los Angeles, either for the Dodgers or the Angels, and that he had "no interest" in playing for anyone else. Miami Marlins On December 10, 2014, the Dodgers traded Haren, Dee Gordon, and Miguel Rojas, to the Miami Marlins in exchange for Andrew Heaney,