Today, it was my mistake because we had different balls...

Today, it was my mistake because we had different balls (than were used in Montreal and Cincinnati). I tried to make it different, my tension for strings was harder here and I tried to make no mistakes because the tension was hard and I had more control. I tried to come back but at 6-5 broke my string. I took my old racket and I lost in the tiebreak. I played really slow, Chela played good today and tried to make winners, and for me, if I play slow I can beat nobody.