After Serena Williams' embarrassing defeat to Simona Halep in the WTA Finals group stage, the American narrowed her eyes at the post-match news conference and said she was looking forward to having a chance to avenge the loss. She didn't have to wait long. The pair will face off again on Sunday in the final of the season-ending championships after winning their semifinals on Saturday in contrasting fashion. Williams beat Caroline Wozniacki in a thrilling contest 2-6, 6-3, 7-6 (6) to remain on course for a third straight title, while Halep swept aside Agnieszka Radwanska 6-2, 6-2 to put herself in a position for the biggest title of her career. Read more http://espn.go.com/tennis/story/_/i...ch-simona-halep-wta-finals-championship-match