Novak Djokovic notched an encouraging win in his comeback from an elbow injury when he beat Japan's Kei Nishikori in the first round of the Madrid Open.
Djokovic broke serve late in each set to get past the world No.20 Nishikori 7-5 6-4 after nearly two hours.
The 12-time grand slam winner hasn't made it to the quarter-finals in his previous five tournaments this year and had admitted he returned to tennis too quickly.
The Serbian former world No.1 was aggressive from the start, hitting 26 winners.
"The draw was such that we had to face in the first round, which is a bit strange," Djokovic said.
"But it was a good opening match."
Milos Raonic defeated Nicolas Kicker 6-3 6-2 to set up a second-round encounter with third-seeded Grigor Dimitrov.
Qualifier Dusan Lajovic got past Karen Khachanov 6-3 6-2 to set up a meeting with France's Richard Gasquet, who beat 14th-seeded Tomas Berdych 6-4 6-2 in the tournament's opening match.
In a first-round all French affair, Benoit Paire hit 39 winners to defeat 15th-seeded Lucas Pouille 6-2 6-3.
His next opponent is 19-year-old Denis Shapovalov of Canada, who got past Tennys Sandgren 6-1 6-4 on Sunday.
Other first-round winner on Monday were Argentine 13th seed Diego Schwartzman, Feliciano Lopez, Damir Dzumhur, Federico Delbonis and Mikhail Kukushkin.