We step out into the famous San Siro for a 7pm kick-off local time (6pm UK) on Thursday night.
Mousa - who grabbed a dramatic last-minute equaliser in Lyon to book our place against Inter - was outstanding again in the first leg at the Lane.
He played a key role in the second goal, scored by Gylfi Sigurdsson, after Gareth Bale headed us into the lead. Jan Vertonghen completed the scoring in the second half.
The attitude of the players going into the second leg is certainly one of respect for Inter and a realisation that the Italian giants will look to put matters right back on home soil.
However, there is also the knowledge that if we score, Inter will need five goals to progress.
"It won’t be easy because Inter will be determined to beat us at home," said Mousa, who will play at one of world football's iconic arenas for the first time.
"We have to concentrate on being ourselves and go out there to win, not think about not losing 3-0 or anything like that.
"We have to play our normal game and if we score, that means they have to score five. It's all about going out with the right mentality."