Nadal in Acapulco still testing troublesome knee

 Spain's 11-time Grand Slam champion will conclude a three-tournament Latin American comeback tour in Acapulco, playing in his third ATP clay court tournament in four weeks.

He came back from an injury layoff of seven months to reach the final in Vina del Mar, Chile, and followed up by winning the title in Sao Paulo on February 18.

In Brazil he needed just 78 minutes to beat Argentina's David Nalbandian 6-2, 6-3 in the title match.

But the 26-year-old says he still feels intermittent pain in his left knee and could yet opt out of the hard court tournament at Indian Wells, where men's main draw play begins on March 7.

Nadal is a two-time champion at the BNP Paribas Open in the California desert east of Los Angeles.

That tournament is immediately followed by the Masters Series event in Miami where he has never won.

"Let's see how my knee responds in Acapulco. We will discuss what has happened during these three tournaments and what I thought about it," Nadal said after his Brazil triumph.

"Then we will see if we are ready to play in Indian Wells or not."

Nadal said it wasn't the thought of stepping up against top competition like Novak Djokovic, Roger Federer, Andy Murray and compatriot David Ferrer that caused him to hesitate, nor was it the possible stresses of the hard court surface.

Instead it's just the simple fact that his knee is still not 100 percent.

"It's better and I've been able to compete, but it's still bothering me," he said after arriving in Mexico.

"It's better on some days and worse on others, which isn't ideal for someone like me, because my idea of competing is based on giving it all at all times."

In Acapulco, Nadal is the second seed behind Ferrer, the world number four who will arrive in Mexico fresh from a successful title defence in Buenos Aires.

Ferrer, 30, earned his 20th career title and his second of 2013 on Sunday and will be going for a fourth straight Acapulco crown.

The men's field for this combined ATP and WTA event also includes 2008 champion Nicolas Almagro and Swiss Stanislas Wawrinka, a semi-finalist last year who lost to Ferrer in the Buenos Aires final on Sunday.

The women's field is headed by defending champion Sara Errani.

Nadal may get a chance to ease into the tournament, drawing a qualifier in the first round.

A massive security operation has been mounted for the event, prompted by a gang rape earlier this month as well as the brutal ongoing turf war between drug gangs that has seen the Pacific port and longtime tourist destination become Mexico's deadliest city.

The 4,000-strong security force is three times the size of the city's own police force and will feature army, navy, federal, state and municipal police, a senior Guerrero state government official told AFP.