The Serbian, who recently split from his long-term coach Marian Vajda, is trying to regain his best form again ahead of the French Open.
Streaking forward, Novak Djokovic caught up to the drop shot sliding into a soft-angled answer that left a bemused Feliciano Lopez applauding the second-seed's speed and slick racquet skills.
He was broken three consecutive times in the first set, and once in the second to give Coric a 5-3 lead that he converted to close out the match.
It almost paralleled his first match at Monte Carlo, against Gilles Simon: take a first set against a risky but ultimately much less skilled player, lose the second, and go down a break of serve in the third before coming back to win, aided by some critical gaffes on his opponent's part (Almagro's wild baseline errors, and Simon's poor serving with the match on his racket).
"When I started to control the points more towards the end of the first set and second set, I was hitting the ball pretty clean, creating a few chances", Murray said. "I've been playing at a high level during many weeks". It was first win over a top-100 player this season for the 273-ranked Indian, who outplayed the Ukrainian 6-2 6-4 in one hour and 10 minutes.
The Spaniard takes on Fabio Fognini of Italy for the right to face Australia's Nick Kyrgios, who beat American Ryan Harrison 6-3 6-3. In their two previous encounters at Madrid, Nadal saved three match points to overcome Djokovic in a classic 2009 semi-final, before the Serb returned the favour in the 2011 final.
Nishikori will play in the third round against Spaniard David Ferrer, who advanced after 10th-seeded Jo-Wilfried Tsonga of France withdrew before the match because of a shoulder injury.
'That's why I chose not to play today'.
Nadal is now 13-0 on clay this year as he swept aside Belgian ninth seed David Goffin 7-6 (7/3), 6-2 much to the delight a boisterous home crowd under the roof on the Manolo Santana centre court.
"It's the first match without my team that's been with me for 10 years", he said. "I'm expecting the best Djokovic tomorrow". He went on to reach four Masters quarter-finals, and was now aiming for his first in Madrid.
"I feel a little bit unusual".
Murray has won only one tournament this season and hasn't made it past the semifinals in the three clay-court tournaments he has played.