(Sports Network) - Phoenix-born lefty Dallas Braden makes his ninth start of the season tonight when the Oakland Athletics open a three-game weekend series with the Baltimore Orioles at Camden Yards.

Braden began 2008 in the Oakland bullpen and make nine appearances, going 1-0 with a 4.80 earned run average in 15 innings of work.

He made start No. 1 on July 22 and beat Tampa Bay with five innings of five- hit, one-run ball, and is 3-3 overall as a starter in 47 2/3 innings.

Braden reached the majors last season with the Athletics and was 1-8 in 20 appearances - 14 starts - over 72 1/3 innings, posting a 6.72 ERA.

He's 2-1 in three career meetings with the Orioles, allowing just seven hits and two runs in 15 1/3 innings.

For Baltimore, lefty Chris Waters makes the seventh start of this, his rookie season.

The 28-year-old Floridian debuted with a 3-0 defeat of the Los Angeles Angels of Anaheim on Aug. 5, allowing just one hit in eight scoreless innings.

He improved to 2-0 with an 11-6 win against Boston on August 20, but is winless in two outings since, including a 4-3 loss to the Chicago White Sox and a no- decision after allowing eight hits and five runs in 4 1/3 innings against the Rays.

Overall, in 33 big-league innings, he's allowed 37 hits and 20 runs while walking 16 batters and striking out 14.

On Thursday in Kansas City, Joey Gathright's RBI single in the 10th inning led the Royals to a 5-4 victory over Oakland in the first game of a doubleheader from Kauffman Stadium.

Jack Cust hit a two-run double and Joey Devine (4-1) was charged with the loss in 1 1/3 innings of work for the Athletics. Dana Eveland started on the hill and gave up four runs on 10 hits in six innings of play.

Jose Guillen went 2-for-4 with three RBI and a run scored as the Royals swept the doubleheader with a 9-6 win in the nightcap.

On Wednesday in Boston, Alex Cora scored the game-winning run in the ninth to help the Red Sox to a 5-4 win over the Orioles to complete a three-game sweep at Fenway Park.

Aubrey Huff went 2-for-4 with a run scored and Lance Cormier started on the mound and gave up just two hits in three innings of work for the Orioles, who have dropped their last six games.

Cormier started in place of ace Jeremy Guthrie, who was skipped a turn in the rotation due to a tired arm.

The Orioles went 0-6 on their road trip, during which time they allowed 60 runs.

Oakland swept a three-game series from the O's in early May.