Katie Boulter responds to Sonay Kartal run by backing up Japan Open win

Katie Boulter has reached the quarter-finals of the Japan Open tennis tournament, putting her one win away from reclaiming the British No 1 ranking. Her run comes in response to fellow British player Sonay Kartal's strong recent performances. Boulter had previously won the Japan Open title and is backing up that result with another deep run in the tournament.