Midseason acquisition Jake Arrieta makes his third start in a Chicago uniform on Wednesday night, when the Cubs host the Washington Nationals in game three of a four-game set at Wrigley Field.

The 27-year-old Missouri native was drafted by the Baltimore Orioles in 2007 and made 69 appearances with them through June 17 before he was sent to the Cubs in exchange for righty Scott Feldman as part of a four-player deal on July 2.

He made his Cubs debut on July 30 and turned in six innings of two-hit, one- run ball while getting a no-decision in a game Chicago ultimately lost, 3-2.

He got start No. 2 on Aug. 16 and was equally effective, tossing seven innings of scoreless two-hit ball, this time en route to a 7-0 defeat of St. Louis in Chicago.

In five 2013 appearances with the Orioles before the trade, Arrieta was 1-2 with a 7.23 earned run average in 23 2/3 innings.

He's 0-1 in four career starts against the Nationals.

For Washington, righty Ross Ohlendorf makes his third start in his 11th appearance of the season.

The 31-year-old had a pair of wins in his initial five relief turns of the season, and has since mixed in a pair of starts while compiling five straight no-decisions since July 6.

He allowed a combined 12 hits and three runs in 13 innings of starts against the Los Angeles Dodgers and New York Mets on July 21 and 26, then returned to the bullpen for a one-third inning stint at Detroit on July 31.

Ohlendorf is 2-0 in six career starts against the Cubs, with a 2.75 ERA in 36 innings.

On Tuesday night, Dan Haren threw six innings of one-run baseball and the Nationals defeated the Cubs, 4-2.

Haren (8-11), who gave up just five hits and struck out six, has not registered a loss since July 22 against the Pirates. He's won four straight decisions.

Ryan Zimmerman, Ian Desmond, Tyler Moore and Denard Span had an RBI apiece for the Nationals, who came into the game having lost four of their previous five contests.

Brian Bogusevic and Donnie Murphy each hit a home run for the Cubs, who saw starter Chris Rusin (2-3) surrender two runs on 10 hits and a pair of walks over 5 2/3 innings.

The Cubs won two of three when the teams last played in Washington from May 10 to 12.