Carmona opened the year with wins in four of his first five decisions, but has lost his last four starts. His latest setback came on Monday against Boston, as he surrendered three runs (two earned) and five hits in six-plus innings. Carmona, though, walked six batters and fell to 4-5 on the season to go along with a 3.53 earned run average.
The 26-year-old right-hander lost his only other start to the Nats back in 2007.
Cleveland drew first blood in this series on Friday, as former Nat Austin Kearns homered twice and knocked in four to back a solid outing from Jake Westbrook in the Indians' 7-2 win.
In 7 1/3 innings, Westbrook (4-3) allowed just two runs on seven hits and two walks while fanning five to lead Cleveland to its third straight win.
Travis Hafner went 2-for-3 with a double and solo home run for the Indians, whose manager, Manny Acta, was fired by the Nationals in midseason last year.
Hafner's last five hits have gone for extra bases.
Adam Dunn and Ivan Rodriguez each had two hits and an RBI, while Luis Atilano (5-3) was credited with the loss for allowing six runs -- three earned -- on seven hits and two walks in five-plus innings for Washington, which was coming off a three-game sweep of the Pirates.
Since returning from the disabled list, Rodriguez is 5-for-11 with two doubles.
Tonight, the Nats will turn to righty J.D. Martin, who is 0-1 in two starts with a 2.31 ERA. Martin did not get a decision in his last start back on June 3 against Houston, as he allowed three runs (two earned) and eight hits in 5 2/3 innings.
This will be his first-ever start against the Indians.
The Nationals took two of three from the Indians the last time these teams met back in 2007.