In the women's event, outraged Pliskova is eliminated in controversial circumstances while world No 1 Halep sails past Osaka
Nadal and Djokovic remain on course for Italian Open semi-final showdown
Rafael Nadal and Novak Djokovic remain on course for a semi-final showdown at the Italian Open after both players eased into the third round yesterday.
Nadal, the world No 2 and seven-time champion in Rome, was in devastating form in the Italian capital, brushing aside Damir Dzumhur of Bosnia and Herzegovina 6-1, 6-0 in just over an hour.
Djokovic, a four-time winner of the Italian Open, also had little trouble in his second round match, defeating Georgia's Nikoloz Basilashvili 6-4, 6-2 in one hour and 18 minutes.
For Nadal, it was the ideal response after his surprise defeat to Austria's world No 8 Dominic Thiem in the Madrid Open quarter-finals that also saw the Spaniard lose his No 1 ranking.
Djokovic, meanwhile, has now secured convincing back-to-back wins in Rome as the Serbian continues to feel his way back after the elbow injury that kept him sidelined for half of last season and prolonged spells this year.
As a result of his absence, former world No 1 Djokovic is ranked a comparatively low 18th in Rome and find himself on the same side of the draw as Nadal. Should both players win two more matches, it will set up a last-four clash between rivals more accustomed to meeting in the Italian Open final.
Nadal, 31, and Djokovic, 30, have faced off in the Rome showpiece four times, winning two apiece.
However, before they can look ahead to a blockbuster encounter, Nadal will first have to get past Dutchman Robin Haase/Canadian Denis Shapovalov, while Djokovic next faces Spain's Albert Ramos-Vinolas, who defeated American John Isner yesterday.
Home favourite Fabio Fognini produced the performance of the day, the Italian world No 21 defeating sixth seed Thiem 6-4, 1-6, 6-3 to send the fans inside Court Centrale into raptures.
In the most high-profile match on Day 4, Japan's Kei Nishikori battled past world No 4 Grigor Dimitrov 6-7, 7-5, 6-4. Nishikori, currently ranked No 24 as he continues his return from injury, was down breaks in both the second and third sets before fighting back to claim a hard-fought victory.
In the women's event, world No 1 Simona Halep was in ruthless form against Japan's Naomi Osaka, the Romanian needing just 59 minutes to win 6-1, 6-0 to reach the third round. The victory not only allowed Halep to exact revenge on Osaka following their one-sided clash at Indian Wells, but ensured the Romanian retains her top ranking.
World No 5 Karolina Pliskova was eliminated by Maria Sakkari in controversial circumstances, prompting the Czech to react by smashing her racket against the umpire's chair at the end of the match.
With the score at 6-3, 3-6, 5-5 and serving at 30-30, Pliskova had an overhead smash incorrectly called out, and after the umpire, Marta Mrozinska, could not find the ball mark the original call stood. Replays clearly showed the ball not to be out, and Pliskova soon called for the supervisor who sided with the umpire.
A clearly angry Pliskova then lost the following point and subsequently the game before her Greek opponent served out the match to take her place in the third round.
"The worst i have ever seen @wta and I hope this lady Marta Mrozinska will never ever judge any match of me or Karolina again," Pliskova's twin sister Kristyna wrote on Twitter.