CHICAGO -- The Kansas City Royals have not captured a series victory since May and have lost 11 of their last 12 games.

Injuries have decimated the starting rotation, which took another hit Wednesday when right-hander Ian Kennedy was placed back on the 10-day disabled list with a left oblique strain.

Kennedy had just been activated off the disabled list on Tuesday after being sidelined since late June with another oblique strain. He pitched three innings and left with soreness in his side. A day later, he was back on the DL as the Royals prepare to begin a three-game series against the Chicago White Sox on Friday at Guaranteed Rate Field.

"All week, the last 10 days, everything has been getting better," Kennedy told reporters after the Royals' 9-4 victory over the Minnesota Twins on Tuesday. "It felt great all night, and then all of a sudden I felt something at the bottom of my ribs. ... It's just aggravating."

Tuesday's victory snapped a 10-game losing streak before Kansas City's bullpen failed to protect a lead on Wednesday as the Royals dropped yet another series. Mike Moustakas hit two home runs in the 8-5 loss after struggling from the plate throughout June.

The Royals hope to rebound against the White Sox. Right-hander Brad Keller hopes to do the same.

Keller (2-3, 2.52 ERA) will start for the Royals after struggling in his last outing. Keller allowed a career-high four runs and a career-high five walks in just 4 2/3 innings in a 15-4 loss to the Boston Red Sox. Keller will make his first start of his career against the White Sox, against whom he is 0-0 in three career relief appearances, all coming this season.

The White Sox snapped a six-game losing streak on Wednesday with a 4-0 victory over the St. Louis Cardinals. As the White Sox contemplate what moves they will make as the trade deadline approaches, they will try to get things figured out against the Royals.

First baseman Jose Abreu, who was named to the American League All-Star team as a starter earlier this week, has been in a slump of late, but like the rest of his teammates, is trying to stay positive.

Abreu is hitting .253 with 12 home runs, but he is batting just .178 with three homers since May 27. He went 0-for-8 with an RBI groundout in the two games against the Cardinals.

"He has had a tough stretch. These things happen," White Sox general manager Rick Hahn told reporters this week, according to the Chicago Tribune. "We've seen All-Star-caliber players such as him go through 20- or 30-game stretches where they haven't performed up to an All-Star level, which happens over the course of a long season.

"It's certainly nothing to be concerned about from our standpoint from a long-term performance standpoint."

James Shields, who could be among those being traded at the deadline, will start Friday against the Royals.

Shields (3-10, 4.53 ERA) is coming off a rough outing in which he allowed a season-worst eight earned runs and 10 hits in 5 2/3 innings during a 12-6 loss to the Houston Astros. Shields is 8-2 in 14 career starts against the Royals, and he beat Kansas City on March 29 this season, allowing five hits and four runs over six innings in a 14-7 victory.