The difference for Darvish is with the strength in his fastball, Dempster said. So how can the Cubs help Darvish find his better form? Dempster explained that his message would be simple and direct.
"Your stuff is so good that I dare you to try to give up as many home runs as you can on your fastball," Dempster said. "His fastball is so good."
Darvish, 32, is 2-3 with a 5.40 ERA in his second season in Chicago. In his most recent start, he struck out seven Marlins while walking six over only four innings of work.
Despite his struggles, the Cubs have remained confident that Darvish can turn this performance around, and Dempster feels the same.
"I'm telling you, it's coming," Dempster said. "It's getting so close. It's getting better and better. (Manager Joe Maddon) is doing a great job of putting him in positions to succeed, taking him out when he's having success, and that just builds and builds and builds. This guy has the ability to punch out 15 batters any given day."