CHICAGO -- White Sox general manager Rick Hahn came up with a catchy phrase to describe his team's disappointing season.

Chicago is 1-6 in the second half, tumbling to fourth place in the American League Central standings and 7 1/2 games back in the wild-card race. Since the White Sox had the second-best record in the majors at 23-10 on May 9, they have gone 23-39.

"We've been wrestling with being a couple games over, a couple games under .500 for the last few weeks. We're mired in mediocrity," Hahn said Thursday before the White Sox's 2-1, rain-shortened loss to the Detroit Tigers. "That's not the goal. That's not acceptable. That's not what we're trying to accomplish for the long term. It may well be a decent turnaround in a short period of time, but the goal was to put ourselves in a situation to win a championship."

Hahn said the White Sox have ruled out adding "short-term rentals" through trades, but they are otherwise open-minded to altering the team.

"We're looking for multiyear fits and the ability to put us in a stronger competition to compete, ideally for this year, but certainly as important, if not more so, for the long term," Hahn said.

The White Sox (46-49) continue their four-game series against the Tigers on Friday night.

Right-hander Michael Fulmer -- a candidate for American League Rookie of the Year -- will take the mound for Detroit in his first career start against the White Sox. Fulmer is 9-2 with a 2.13 ERA overall, 7-1 with a 0.83 ERA in his last 10 starts. The 23-year-old allowed two runs in a career-high eight innings against the Kansas City Royals on Sunday.

"I don't think his heart rate changes," Tigers manager Brad Ausmus told the Detroit Free Press.

The Tigers (50-46) are 4-3 after the All-Star break and four games back in the AL wild-card race.

White Sox right-hander Jacob Turner (0-1, 18.00 ERA) will start Friday. Chicago purchased his contract on Sunday from Triple-A Charlotte, where he was 4-7 with a 4.71 ERA in 18 starts. He is filling in for left-hander Carlos Rodon, who went on the disabled list earlier this month due to a sprained left wrist.

Turner allowed eight runs and seven hits in four innings Sunday against the Los Angeles Angels in his first major league start of the year.

"Obviously, you work hard to get back here, and you appreciate any opportunity you get," Turner said after the outing in Anaheim. "From that standpoint, you realize all the work you put in to get back here. But you have to go out there to win the game and to execute pitches, and there were too many pitches today I didn't execute."

Turner will be facing his former team for the first time -- Detroit drafted him ninth overall in 2009. He was 1-2 with an 8.28 ERA in six starts with the Tigers in 2011 and 2012.

"I had a lot of good memories there," Turner said. "I obviously made my major league debut there, so I'm always grateful for the opportunity they gave me in professional baseball, but I don't think at this point in my career there's anything extra in pitching against them."