Sixth seed Thiem crashed out just a week after inflicting a first clay-court defeat on Nadal in over a year in Madrid which cost the Spaniard the world number one ranking.The 24-year-old destroyed his racket in fury as he suffered his first defeat to Italian Fabio Fognini in three meetings, sinking 6-4, 1-6, 6-3 at the Foro Italico. He broke in the 11th game and later served out the set.
Top seed Rafael Nadal on Wednesday opened his final pre-French Open event with a 6-1 6-0 win over Bosnia's Damir Dzumhur to reach the Italian Open third round in Rome. "It was important, after a loss in Madrid, to come back strong". "And that's what I did today".
Nadal, who is aiming for an eighth title in the Italian capital, looked in imperious form as he saw off Dzumhur in just 61 minutes.
Djokovic, a four-time victor 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.
Bulgarian third seed Grigor Dimitrov also suffered an early exit, going out to Japan's Kei Nishikori after a marathon 6-7 (4/7), 7-5, 6-4 battle.Former world number one Karolina Pliskova was so angry she put a hole in the umpire's chair with her racket instead of shaking hands after losing to Greece's Maria Sakkari.
Halep needs to reach at least the quarterfinals or risk losing the top spot to Caroline Wozniacki. Djokovic, a four-time victor at Rome, had five aces in the match and will next face Spaniard Albert Ramos-Vinolas, who rallied past eighth-seeded American John Isner 6-7 (5), 7-6 (2), 7-6 (5) in two hours, 53 minutes.
Osaka had every reason to be confident heading into her clash with Halep after beating her 6-3, 6-0 at Indian Wells in March, but on this occasion, she collapsed after a wasteful start.
The Spaniard can reclaim the world number one ranking from Roger Federer if he wins a record-extending eighth title in Rome this week.
"We're finally connecting and I think that's the most lovely thing", Fognini said of the crowd, which whistled him off the court following an erratic performance a few years ago.
Get breaking news alerts. After two victories in two weeks, Zverev became the youngest victor of the tournament since Rafael Nadal who won it at the age of 19. Croatia's Marin Cilic, the No. 4 seed, rallied past American Ryan Harrison 6-7 (3), 6-1, 7-6 (1) while fifth-seeded Argentine Juan Martin del Potro ousted Greek qualifier Stefanos Tsitsipas 7-5, 6-3.
US Open champion Sloane Stephens will play France's Caroline Garcia for a quarter-final place.
She could not hide her fury as she went on to lose the match 3-6, 6-3, 7-5.