The striker has agreed a season-long loan with Lierse and will likely make his first appearance against Club Brugge next week.
The approach was a surprise, but Watt was convinced to make the move by Israeli Gershon, who now plays for Waasland-Beveren.
"It happened very fast," Watt explained. "I was told on Friday and I thought it was a good opportunity for me. I spoke to my mate Rami Gershon and he told me all about it and said it was a good opportunity for me, so hopefully I can score some goals. I know Lierse don't have an out and out striker who is fit just now so hopefully I can come in and score some goals."