Rising Australian tennis star Nick Kyrgios’ injury comeback has fallen flat with a three-set defeat to world No.192 Elias Ymer at the Barcelona Open.

Second-seeded Rafael Nadal, meanwhile, had a much more enjoyable start to his campaign, avenging last year’s loss to Nicolas Almagro by beating his fellow Spaniard 6-3 6-1.

World No.44 Kyrgios, who has been sidelined with an ankle complaint since his second round loss to Grigor Dimitrov at the Indian Wells Masters a month ago, blew multiple chances to overcome his 19-year-old opponent before going down 2-6 7-5 7-6 (9-7) in just under two-and-a-half hours on Wednesday.

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The 16th seed, playing in his first ATP Tour event as a seeded player, jumped out of the blocks to breeze through the first set in typically cavalier fashion before losing a tightly-contested second set 7-5.

The Wimbledon and Australian Open quarter-finalist, who turns 20 next week, then raced out to a 3-0 lead in the deciding set only to seize up as his less experienced rival took the ascendancy.

Having forced the tiebreak, Ymer then capitalised to hold a mini break at 5-4, only to lose both points on his own serve, allowing Kyrgios to serve for the match.

He returned the favour, however, and Ymer was able to advance to the third round, where he will face third seed David Ferrer.

Meanwhile, Nadal, who lost last week to Novak Djokovic in the Monte Carlo semifinals, rebounded with a solid performance to advance to the third round.

Almagro upset Nadal on the same red clay court last year to end the eight-time champion’s run of 41 consecutive wins at the tournament he has dominated for almost a decade.

“Nico is a danger because of the potential he has. At the start he served very well and won a lot of points on the second stroke,” said Nadal.

“It was difficult, so I decided to step back a metre and put more balls in play and, bar the final game, I controlled the match.

“I committed very few errors and I hadn’t forgotten that he beat me last year.”

Nadal will face 17-year-old Russian Andrey Rublev or Fabio Fognini in the last 16 on Thursday.

In other matches, US Open champion Marin Cilic’s disappointing season continued as he was eliminated by Dominican Victor Estrella Burgos 6-4 6-4 while Santiago Giraldo set up a third-round meeting with top seed and defending champion Kei Nishikori with a 6-3 3-6 6-1 over Portugal’s Joao Sousa.