Federer: I did not underestimate Ramos-Vinolas

Defending champion Roger Federer insists he did not underestimate Albert Ramos-Vinolas in their second-round clash at the Shanghai Masters on Tuesday.

The Swiss world number three slipped to a shock 7-6 (7-4) 2-6 6-3 defeat at the hands of his Spanish opponent, who is ranked 67 places lower.

But 17-time grand slam champion Federer claims he was not caught off guard, having come close to elimination at the same stage on his way to winning last year's tournament - edging past Leonardo Mayer on that occasion.

''I'm always cautious,'' Federer said. ''I don't underestimate or lack respect for anybody out there.

"These guys are all touring professionals, they know what they're doing.

"I just think the first round here in Shanghai has always been historically quite difficult, getting used to the conditions and the surface and the balls.

''Last year I got lucky. This year I didn't. So it's a pity.''

Before beating Federer, Ramos-Vinolas had a 0-15 record against top-10 opposition.