Hellickson is hoping for different results than the last time he faced the White Sox, when he gave up five runs on five hits over six innings in Chicago on April 25.
"They've got some really good hitters in the lineup," he said. "I'm going to have to be at the top of my game again."
Keeping his walk total down will be key. Hellickson issued four free passes in Chicago.
"It was early in the year," he said. "I wasn't too good. It was during that stretch where I had a few walks, and then give up the big hit. Nothing was really going right at that time. Hopefully tomorrow will be a little different.
"I've been able to get ahead with all three of my pitches. I wasn't able to do that early in the year. The confidence is a little bit higher now, too."
Glenn Sattell is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.