In-form striker Michu had a quiet game but still went the closest to scoring with a fine chip which Everton goalkeeper Tim Howard tipped on to the bar.
Swans boss Michael Laudrup said: "If Del Bosque had called me before, I could have told him it wasn't the best game to see Michu.
"But in Spain they are watching the Premier League and Del Bosque knows exactly what Michu has done until now, so I think it was just a visit. I think he has already made up his mind about Michu.
"We say often about Michu - he gets one chance and he nearly scores a goal again. Like the other day - one-and-a-half, two chances and he scores. That is really class."