Watch: Murphy burns Harvey with 1st career HR vs. Mets

Daniel Murphy is the hottest hitter in baseball, and he made his former club pay on Thursday when he continued his torrid pace toward hitting .400.

In the first inning of the Washington Nationals' contest against the New York Mets, Murphy squared off against Matt Harvey for the first time in his career and took the right-hander deep to center field for a two-run homer.

The long ball was Murphy's first career homer at Citi Field as a visiting player, according to ESPN Stats & Info.

Murphy, who was down 0-2, pushed his batting average to .420 (21-for-50) when behind in the count this season.

The 31-year-old infielder was a big part of the Mets' postseason success last year, but departed for Washington in the offseason after receiving a three-year, $37.5-million contract from the Nationals.

Prior to Thursday's game, Murphy was hitting .395/.424/.612. No one has hit .400 in a season since Ted Williams hit .406 in 1941.