Petra Kvitova admits to nerves

Newly-installed world number three Petra Kvitova has confessed to being nervous before making her WTA Championships debut this afternoon.

The Wimbledon champion finalist beat against Vera Zvonareva in straight-sets, although she struggled at times during the second set.

"I was very nervous," the 21-year-old said after her victory. "I couldn't move before the match and my stomach was turning around.

"It was important to win my first match."

Kvitova and Zvonareva are in the Red Group along with world number one Caroline Wozniacki and Agnieszka Radwanska.