The young striker joined the Belgian side on a season long loan deal at the weekend rather than accept offers to stay in the SPL.
Belgian football is on the rise thanks to the performances of the national team who draw players from all over Europe including stars such as Vincent Kompany, Axel Witsel and Christian Benteke.
Those players all emerged in Belgian football which has also provided an opening into Europe for African players such as Victor Wanyama.
Lierse are currently in 12th place in the 16 team Belgian league with five points from six matches. Last season they avoided relegation by three points.
Watt will make his debut next Saturday away to Club Brugge who are currently in third place, four points behind leaders Standard Liege who have taken full points from the opening six matches.
Before he makes his Lierse debut, away to Standard Liege next Saturday, Watt will be on international duty with Scotland’s u-21 side facing Holland tonight.
Last month Scotland lost 6-0 to England with coach Billy Stark confident that that reverse was a one off.
“We have to remind them they were doing fine until the England game,” he stated.
“We don’t hide from it, that was obviously a bad night for us. But what you have to do is show that you can bounce back.
“You would maybe look for a slightly easier game than Holland at their place to do that but that’s the game that’s in front of us and it’s a championship game.
“The England game was a friendly, and pride was severely dented, but there was no loss of points.
“We go to Holland and we are not expected to get anything there, which was the same as the England game.
“We didn’t do ourselves justice on that night so we want to do it this time.”