The Seleccao star salvaged a 1-0 victory for Paulo Bento's men with a late header but was left disappointed his side could not manage more than a solitary strike.
The Real Madrid forward scored the only strike of the World Cup play-off first leg at the Estadio da Luz with eight minutes left on the clock, though was unfortunate not to double his tally when he hit the woodwork afterwards.
"It was an important goal and enough to give us the victory," he told reporters after the match. "We could have done with one or two more goals, but it did not happen. We have to be happy with the result and, on Tuesday, we have another battle. We may take to the field with just a minimal advantage, but it's better than a draw.
"It would have been better to have scored another goal, and now we may have to score in Sweden. We will give it our best and nobody wants to miss being in Brazil."
Seleccao coach Paulo Bento insists having the slender advantage will not force the nation to play defensively in the away leg and was delighted with how his charges responded in the second half.
"This is a playoff with two teams that are very balanced," he said. "We knew it was going to be balanced. Now the team is preparing to win in Sweden. We will not go there to defend the result.
"We had a great chance early in the game. Then Sweden responded with a cross, which was virtually their only chance in 90 minutes."
Bento found his players getting better as the match went progressed.
"Overall, in the second half we were much, much better. We were dominating the whole game, but it was more evident in the second half," he said. "We created more scoring opportunities to achieve a better result. The players are to be congratulated for what they did, and for the attitude demonstrated."