Djokovic warned for "unsportsmanlike conduct"
World number two Novak Djokovic on Sunday was warned for "unsportsmanlike conduct" by the chair umpire Carlos Bernardes during his opening win over Austria's Dominic Thiem at the ATP World Tour Finals in London. After losing the first set on tie-break, Djokovic had smacked a ball angrily which went past his backroom staff to an area that contained no seating.