* Top seed Ferrer falls to qualifier
* Nadal made to work by Berlocq (Updates after Nadal win, adds quotes)
April 24 (Reuters) - Top seed David Ferrer summed up his error-strewn defeat by qualifier Dmitry Tursunov as "one of the worst I have played" after falling at the first hurdle at the Barcelona Open on Wednesday.
The Spaniard lost 7-5 3-6 6-1 to the Russian but seven-time champion Rafa Nadal eased past Carlos Berlocq 6-4 6-2.
Four-time finalist Ferrer had pulled out of the Monte Carlo Masters event last week with a thigh muscle injury picked up when losing in the Miami final to Andy Murray last month.
"It was a game to forget, one of the worst I have played," a downcast Ferrer told reporters after his defeat in blustery conditions.
"I wasn't good in tennis terms, mentally, or with my attitude. It affects me personally because my opportunities to win here are getting fewer as I get older," said the 31-year-old.
"Tursunov's been very good, better than me, and in the end that's why he won."
Second seed Nadal, who beat Ferrer in last year's final, started his bid for an eighth Barcelona title with a tough workout against Argentine Berlocq.
The world number five was back in action after losing his Monte Carlo crown to Novak Djokovic on Sunday as he looks to get back to his best form after seven months out with a knee injury.
Nadal, 26, had white strapping under his left knee as he suffered one break of serve in the first set, before really getting the upper hand.
He needed six match points on Berlocq's final service game before breaking to secure his 35th straight triumph at the tournament.
"Carlos is having a good season, playing with Argentina in the Davis Cup against France (where he won the decisive rubber two weeks ago) has given him a lot of confidence," Nadal told Spanish television courtside.
"It was also a tough day with a lot of wind, against an opponent who likes this surface.
"David (Ferrer) has also suffered because of this with a rival who likes to hit the ball very hard. This combination favours surprises." (Reporting by Mark Elkington, editing by Justin Palmer)