Serena Williams re-established her customary superiority, hammering Daria Gavrilova 6-1, 6-2 to reach the second round of the Cincinnati Masters on Monday.
Serena Williams is seeking to regain her top form after missing most of the 2017 WTA season due to a pregnancy.
Two-time Cincinnati champion Serena lost the Wimbledon final to Angelique Kerber last month.
The 23-time Grand Slam winner struggled mightily against the British No. 1.
Serena Williams claimed that she was tested far more frequently than any other player.
Serena Williams moved up one spot in the WTA rankings this week to world No.27.
Serena Williams' husband Alexis Ohanian on Saturday posted a heartfelt message on his Instagram account following the tennis star's loss to Angelique Kerber in the final at Wimbledon.
Angelique Kerber became the first German woman to win Wimbledon for 22 years.
Wimbledon Women's Final highlights, Serena Williams vs Angelique Kerber Tennis Match: Angelique Kerber became the first German to win a Wimbledon singles title since Steffi Graf in 1996.
Serena Williams is on the verge of making more history as the seven-time champion aims to become the first mother to win Wimbledon since 1980.
The 36-year-old American eased past Germany's Julia Goerges.
Serena hasn't won a Grand Slam since the birth of daughter Olympia in September and her last trophy came at the 2017 Australian Open.
If Serena lifts the Venus Rosewater Dish this weekend, she will join an select group of women who have won Grand Slam titles after becoming mothers.
Serena Williams will face Italian world number 52 Camila Giorgi on Tuesday for a place in the semi-finals.
Federer has been in imperious mood in pursuit of his ninth Wimbledon crown, while Williams is rounding into form just as the seven-time champion's rivals have collapsed all around her.
The 36-year-old said she had been in training when Olympia took her first steps.
Serena Williams boosted her chances of winning an eighth Wimbledon and 24th Grand Slam by making the fourth round at the All England Club.
Serena Williams has made it clear that she is excited to compete at Wimbledon, using her Twitter account for the past week to count down the days until Monday, when the tournament begins.
