Earlier, world number one Novak Djokovic stormed into the quarter-finals of the Rogers Cup with 6-2 6-1 demolition of Jack Sock running his Masters 1000 winning streak to 28 matches.
ATP’s rulebook explicitly lays out the rule in Section VIII (i): “Players shall not receive coaching during a tournament match”. The last time he reached the Wimbledon fourth round, he lost out to Novak Djokovic in 2012.