MADRID: Former world number one Novak Djokovic showed signs of a return to form with an impressive 7-5 6-4 victory over Japan's Kei Nishikori in the opening round of the Madrid Open on Monday.

Later France's Gael Monfils beat Georgian Nikoloz Basilashvili 6-2 3-6 6-3 to set up a second round clash on Wednesday with champion and tournament favourite, Rafael Nadal.

Following early exits in Barcelona, Monte Carlo, Miami and Indian Wells, Djokovic, 30, struck his shots with precision and recorded 26 winners to improve his head-to-head advantage to 12-2 against world number 20 Nishikori.

Djokovic was broken to love at 2-2 but he recovered well by pouncing on his opponent's second serve to clinch the opening set in just over an hour.

The two-time winner in Madrid went on to claim a decisive break in the 10th game of the second set to wrap up the contest.

It was Djokovic's first victory over a top-20 opponent since the Serb overcame Monfils at Eastbourne in June last year.

"I was looking forward to have these kind of matches, looking to try to win these kind of matches," Djokovic told reporters.

"So that's why it was really a perfect scenario to start off the tournament. It's great. I couldn't ask for a better start."

Earlier in the day, Canada's Milos Raonic booked a second-round meeting with third seed Grigor Dimitrov, defeating Argentina's Nicolas Kicker 6-3 6-2.

Raonic recorded 17 aces to knock out the Madrid debutant.

Frenchman Lucas Pouille, seeded 15th, crashed out of the tournament after a 6-2 6-3 defeat by compatriot Benoit Paire.

Paire claimed his first victory in four attempts against Pouille and will next face Canadian teenager Denis Shapovalov.