OSIJEK, Croatia (AFP) - Croatia, the 2016 runners-up, and five-time champions Spain were locked at 1-1 on the opening day of their Davis Cup World Group first round clash on Friday (Feb 3).

Croatia, playing without national number one Marin Cilic, led after the opening rubber in which Franko Skugor unexpectedly defeated Pablo Carreno Busta 3-6, 6-3, 6-4, 4-6, 7-6 (8/6).

Skugor, the world number 223, saw off the Spaniard, ranked 26, after a marathon match lasting over four hours.

"I started the match well, returned well after losing the second and third set but lost concentration at the end," said 25-year-old Carreno Busta who is playing for Spain after 14-time major winner Rafael Nadal opted out of the tie.

He admitted the 29-year-old Croatian surprised him.

"I knew that he is a good player but I didn't think he could play so well and endure the pressure. He played the best match in his career." Skugor said: "I simply enjoyed it on the court. I'm fit, well prepared for the season.

"We came here to give our maximum ... that is important, and we will do it." But, in the second rubber the 16th-ranked Roberto Bautista Agut defeated Davis Cup debutant Ante Pavic, the world number 486 - 6-4, 6-2, 6-3.