The Spain international was surprised and thrilled after scoring twice to help his side to a 3-0 win over Nigeria in their final Confederations Cup group game
The Barcelona full-back scored a fine solo effort early on before tapping home his side's third in the closing minutes to secure la Roja's third win from three in their group, and he was thrilled to secure the man-of-the-match award for his efforts on Sunday.
"It's not normal that I have scored twice in a game," Alba told reporters. "I think it's the first time.
"This is new for me, because, as you say, normally this award [for being man-of-the-match] is for strikers or those up front in big games. I'm very proud to receive the award."
Vicente del Bosque admitted his side had struggled with conditions in Fortaleza on Sunday evening, and Alba acknowledged that the heat has posed a few problems for sides during the tournament.
"We felt the heat the whole game, it was incredibly warm," he continued. "Your feet hurt... But it's the same for all the teams."
Spain will now face Italy in the last four in a repeat of the Euro 2012 final, which Spain won 4-0, but Alba insists his side will need to be at their best to overcome Cesare Prandelli's side.
"Against a team like Italy you don't know what to expect," said the 24-year-old. "They're organized at the back and they're great on the ball.
"They'll be tough on us, the way they always have been. We need to maintain our style of play and post a clean sheet at the back."