Juan Carlos has a very good record in Cincy. He was the finalist in 2006 and beat Rafa on his way to the final. He was a semifinalist in 2002 too. It seems the fast surface there suits his hard court game because he can take the ball early. He also has a pretty good record against some big servers from Croatia, like Karlovic and Ancic (not so with Ljubicic though).
It appears Cilic is in the midst of a mini slump, compared to his good form earlier this year. That said, he had one full week to prepare himself for Cincy after losing to Youzhny in an unconvincing manner last week. So I think he must be really bracing himself for the challnge this week, and if his game is on he can cause trouble to many players, including Ferrero.
So I'm expecting a tough match for both but hopefully Juanqui will win!