John Isner isn't a traditional clay-court thinker.

Isner, who beat Marin Cilic to reach his first Rome semifinal, disputes a traditional theory that consistent counter punchers are best built for clay-court success.

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In fact, Isner asserts clay isn't good for grinders.

Pointing to the fact five of the eight Rome quarterfinalists stand 6-foot-5 or taller—Alexander Zverev, Milos Raonic, Cilic, Juan Martin del Potro and himself—Isner asserts big hitters with expansive strike zones are better built for the high-bouncing terre battue.

"That's the bit of the misconception about clay is it's good for grinders. It's not, in my opinion," Isner told the media in Rome. "I think for players that like to hit the ball hard and like to hit the ball at chest level, clay is a great surface for big players like that.

"I always thought that clay is a good surface for me. I'm playing well on it now."

Photo credit: Internazionali BNL d'Italia