Fernando Santos insists he had no problem in leaving Cristiano Ronaldo on the bench as Portugal played out an "interesting result" in their Nations League opener with Spain.

Alvaro Morata fired Spain into a 25th-minute lead with his 26th strike in all competitions for his country, becoming the joint-seventh highest scorer in La Roja's history alongside Emilio Butragueno.

Ronaldo was introduced after the hour mark but it was fellow substitute Ricardo Horta who made the difference.

Horta popped up at the back post with eight minutes remaining to coolly convert Joao Cancelo's low, whipped cross from the right flank, snatching a 1-1 draw for Portugal in Seville.

Santos, speaking after the game, was quick to defend his decision to name Ronaldo among the substitutes, while he hailed the performance of his side on the road.

"There is no management at all. Management will be done in every game. Here too. It seemed to me that this was the best solution for the start of the game," Santos told Sport TV.

"A different team [Portugal], in terms of work and positioning of field, with different things. This seemed to be a good solution and I had Cristiano whenever I needed to get him on the field.

"I already knew that. It's a normal structure."

He added to RTP3: "Thank God. I'm very happy, despite being sad about the result, I'm very happy because a Portugal draw with Spain is just an interesting result.

"Of course, it's not a good result for us, but still good for us, for the working of this group, which leads people to believe that we can do more."

Portugal host Switzerland on Sunday in their next Group A2 game, while Spain visit Czech Republic on the same day.