Serena Williams' bizarre moment with chair umpire in latest victory

Serena Williams was involved in a bizarre exchange with the chair umpire as her return to tennis continued with a second-consecutive win on Wednesday.

The American star moved into the semi-finals of the women's doubles at the Eastbourne International after partnering with Ons Jabeur for a 6-2 6-4 win over Shuko Aoyama and Chan Hao-ching.

Ahead of her return to Wimbledon in the singles next week, there were signs on Wednesday that the 40-year-old is regaining some sharpness after nearly 12 months out.

She produced back-to-back pick-up shots off her toes early in the first set and reeled off three-straight aces on break points in the second game of the second set.

Williams' serve - the biggest the women's game has ever seen - was increasingly impressive when under the pump. 

And it was the 23-time grand slam singles champion who served out the victory.