Sloane Stephens’ 6-4 6-0 win over Pauline Parmentier in Acapulco marked the American’s first victory since winning the US Open in 2017.
Since that breakthrough Grand Slam triumph, Stephens endured a losing streak spanning five months and eight matches.
The American finally returned to the winner’s circle with that commanding win on Tuesday, getting the job done in a snappy 74 minutes to take her place in the second round.
.@SloaneStephens topples Pauline Parmentier 6-4, 6-0!
— WTA (@WTA) February 27, 2018
There she’ll face qualifier Arantxa Rus, who beat wildcard Kayla Day 4-6 6-1 6-0.
Stephens, the top seed this week, won the Acapulco title in 2016.
Canadian teenager Denis Shapovalov scored another big scalp with a three-set victory over Kei Nishikori.
After a tense first set which Nishikori claimed in a tiebreak, the 18-year-old wore down his opponent – 10 years his senior – to win 6-7(3) 6-3 6-1 in two hours and 17 minutes.
Shapovalov, who in 2017 stunned Rafael Nadal in Montreal and upset Jo-Wilfried Tsonga at the US Open, is expected to take on Dominic Thiem in round two, should the third seed get past qualifier Cameron Norrie.
Fifth seed Juan Martin del Potro brushed aside the floundering Mischa Zverev to set up a second-round clash with David Ferrer.
— Tennis TV (@TennisTV) February 28, 2018
Del Potro beat Zverev – who’s lost nine of his past 11 singles matches – 6-1 6-2 in just 61 minutes on Tuesday local time.
Defending champion Sam Querrey was unable to join del Potro and Shapovalov in the last 16, bowing out in the opening round to Australian Matt Ebden.
Ebden needed four match points to see off the seventh seed, winning 6-3 1-6 7-6(5) to claim his biggest victory – in ranking terms – in six years.
In another result, Australian Open semifinalist Hyeon Chung beat Donald Young in straight sets.
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