Tyson Beckford -- Ronaldo's GF Can Save Portugal ... With Her Genitals

Only one person can save Team Portugal from World Cup humiliation -- Irina Shayk ... so says male supermodel Tyson Beckford who says the power lies squarely ... in her crotch.

Beckford -- a huge Portugal fan -- was out watching futbol at Serafina restaurant in NYC yesterday when he tried to explain why Cristiano Ronaldo crapped the bed during Game 1 against Germany.

"It's either the World Cup jitters ... or he's just too sexy to be playing!"