The White Sox have lost two straight and five of their last seven games, including Wednesday's 8-0 loss to the LA Angels of Anaheim in the finale of a quick two-game series at the Big A.
Zach Stewart was hammered for seven runs and seven hits in six innings to suffer the loss, while Alexei Ramirez had a team-best two hits.
"Today is one of those days you throw away and come back the next day," White Sox manager Ozzie Guillen said.
Guillen's ballclub is seven games behind Detroit for the AL Central lead, with Cleveland in second place at 6 1/2 games off the mark.
Jake Peavy will toe the rubber for the Pale Hose tonight and he's 5-6 with a 5.06 ERA in 16 games (15 starts) this season. Peavy is just 1-5 in his last six decisions and was beaten by Texas the last time out in a 7-4 loss on Aug. 19 at U.S. Cellular Field. He gave up seven runs and six hits in six innings.
Peavy, a right-hander, has been reached for 11 runs over his last two starts and is 2-1 in six road assignments this season. In six career starts against the Mariners, Peavy is 4-1 with a 4.00 ERA.
Seattle has won two straight and three of four games, and went 3-4 on a recent road trip against Tampa Bay and Cleveland. In Wednesday's 9-2 win over the Indians at Progressive Field, Wily Mo Pena went 3-for-3 with a home run and four RBI and Kyle Seager posted four hits, including three doubles, three runs scored and an RBI for Seattle, which got three hits from Dustin Ackley and has scored 26 runs over its last three games.
"He had a big day for us out there today," said Seattle manager Eric Wedge about Pena. "He's so strong. When he steps up there he can really hit the baseball and change the game."
Mariners ace Felix Hernandez improved to 12-11 this season with six innings of two-run ball and 10 strikeouts.
Charlie Furbush draws the start for Seattle tonight and he's 2-2 with a 6.30 ERA in five games (4 starts) with the club. He lost at Tampa Bay on Saturday in an 8-0 decision and yielded five runs and eight hits in three innings. He has no record and a 2.70 ERA in two relief appearances against the White Sox.
The Mariners will also host the LA Angels of Anaheim for four games on this seven-game homestand.
Chicago has won four of six meetings so far with Seattle this season and is 13-3 in this series since the start of the 2010 campaign.