Novak Djokovic found his form again to reach the last 16 of the Madrid Open with a routine win over Borna Coric on Wednesday.
Djokovic, having been dumped out of the Monte Carlo Masters in the second round by Jiri Vesely last month, was rarely tested by Coric en route to a 6-2 6-4 at the clay-court tournament.
His win sets up a third-round meeting with Roberto Bautista Agut, a three-set winner over Spanish compatriot Feliciano Lopez.
Kei Nishikori - a finalist at the Barcelona Open last month - needed three sets to see off Fabio Fognini, while Thomas Berdych and David Ferrer are through following wins over Denis Istomin and Denis Kudla respectively.
French seventh seed Jo-Wilfried Tsonga outlasted Albert Ramos-Vinolas 7-6 (8-6) 5-7 6-4, though 2009 US Open champion Juan Martin del Potro fell 6-4 7-6 (7-2) to Jack Sock in two sets.
But world number four Stan Wawrinka is out after a surprise defeat to Nick Kyrgios, who won two tie-breaks to progress along with Sam Querrey - the American beating Lucas Pouille 6-7 (5-7) 6-3 6-4 to seal an encounter with Rafael Nadal.
DJOKOVIC HAPPY WITH RETURN TO FORM
Djokovic, who is bidding to become the first man to win 29 ATP Masters 1000 titles, needed only an hour, 18 minutes to see off Coric and expressed satisfaction with how he performed against the Croatian teenager.
"[It] was a satisfying performance against a young player that I had never played against, somebody who was in form," Djokovic said. "I watched his match against [Nicolas] Almagro, who won a tournament last week, and he beat him comfortably. That deserves respect.
"We know each other well. We've practiced many times. I do see myself in him a little bit. We play a similar style. He's a great fighter. For his age, he's quite mature and mentally tough.
"We have a very nice relationship. [This] was the first official match we've played against each other, so I was happy with my performance. It was a fun match to be part of."
WAWRINKA CRASHES OUT
With a pair of wins over Tomas Berdych and victories over Marin Cilic, Richard Gasquet and Milos Raonic to his name in 2016, Kyrgios was always likely to prove a troublesome opponent for Wawrinka.
And that proved to be the case as the world number 21 edged an encounter in which neither man dropped serve.
The often controversial Kyrgios, whose win over the Swiss at last year's Rogers Cup is remembered more for his comments towards Wawrinka than any of his play in that contest, did not face a break point in the match.
It was the 21-year-old who had the edge in the pair of tie-breaks, coming through 7-6 (9-7) 7-6 (7-2) in one hour, 45 minutes.
NISHIKORI AND FERRER SURVIVE SCARES
After his run to the Barcelona showpiece, Nishikori will have been expected to sweep past Fognini, ranked 25 places below him.
But the Italian made life hard for the world number six, forcing a third set and breaking for a 4-3 lead in the decider before Nishikori won four of the last five games to emerge a 6-2 3-6 7-5 winner.
Ferrer had similar difficulties against American Kudla, who pushed the home hope all the way in a match that lasted two hours, 15 minutes.
Kudla, 52 places below Ferrer in the rankings, refused to lie down and levelled at 2-2 in the third having lost serve at the start of the set, only for Ferrer to seize the initiative again and ensure a 6-4 4-6 6-4 success and a third-round meeting with Berdych.
BERDYCH BREEZES PAST ISTOMIN
While Nishikori and Ferrer were provided with testing second-round matches, Berdych had no problems in defeating Istomin.
The Czech, a runner-up at the tournament in 2012, needed just an hour and nine minutes to win 6-3 6-3.
Berdych had beaten Istomin in all of their four previous meetings on the Tour and was dominant in this match.
The world number eight converted four of his five-break point chances in a clinical showing, but his road to a potential final gets tougher now as he faces Ferrer.
Djokovic and Nadal will headline Thursday's action against Bautista Agut and Querrey, while Andy Murray takes on Gilles Simon.
Nishikori's reward for beating Fognini is a tough meeting with Richard Gasquet and Berdych's clash with Ferrer promises to be an entertaining one.
Kyrgios will be out to continue his momentum against Uruguay's Pablo Cuevas.