Dominika Cibulkova, who won the title in Stanford last month, says she is mentally exhausted after playing five straight weeks.

“I was mentally tired today,” she told reporters after her 3-6, 6-3, 6-3 loss to Klara Zakopalova in New Haven. “I didn’t have the energy to fight to win this match. Usually I get very negative. I make things much worse than they are. I make it tough for myself.”