World number 28 Verdasco became frustrated after a delay in receiving his towel between points
A Wimbledon chief has called for greater "mutual respect" after a video clip showed Fernando Verdasco gesturing at a ball boy to hurry up with a towel during last month's Shenzhen Open.
Mick Desmond, commercial and media director of the All England Club, added he was "not afraid" to fine players.
Billie Jean King says Serena Williams was "totally out of line" for her outburst in the US Open final, but also believes umpire Carlos Ramos "blew it".
Williams, beaten in straight sets by Naomi Osaka, was docked a game for verbal abuse, having already had a point penalty for smashing her racquet and a code violation for coaching.
Novak Djokovic has won back-to-back Grand Slam titles for the first time since June 2016
Novak Djokovic produced an impeccable performance to beat Juan Martin del Potro in the US Open final and win his 14th Grand Slam title.
The 31-year-old Serb won 6-3 7-6 (7-4) 6-3 to earn his third triumph in New York and equal American great Pete Sampras' haul of major trophies.
Ms Osaka is the first Japanese player to win a grand slam title; Ms Osaka beat Ms Williams 6-2 6-4
Japan is celebrating its first ever Grand Slam tennis win after Naomi Osaka's US Open win over Serena Williams 6-2 6-4 at Flushing Meadows.
Osaka stayed calm as Ms Williams went into meltdown after the umpire imposed a series of penalties.
Serena Williams was fined $17,000 (£13,100) for the code violations that included calling the umpire a "liar" and "thief" in her US Open final loss.
Williams, beaten by Naomi Osaka, was docked a game for verbal abuse and had a point penalty for racquet smashing and a code violation for coaching.
