The striker, who shot to stardom last season with a memorable goal against Barcelona at Parkhead in the Champions League, has seen his career nosedive after being sent on loan in August.
He was immediately criticised by Menzo over his physical condition, to which Watt responded by whipping his shirt off to celebrate after netting one of just two goals he has scored for the ProLeague side.
He was then sent off just 30 seconds after coming on as a substitute in a match against Charleroi.
Most worryingly of all, reports in Belgium claimed Watt has been sent home twice from training for refusing to follow Menzo's instructions. He's also lost his Scotland Under-21 place.
Watt, who will be 20 on December 29, was ditched entirely from Lierse's 18-man squad for last night's crucial Pro League relegation clash with Waasland-Beveren.
And Menzo, his patience finally having snapped, left the teenager in little doubt as to why he had been axed.
He said: "I have selected 18 players who understand what it is all about in our next two matches and just how crucial they are. Tony does not seem to realise this.
"It's clear to me at present Tony does not know what he's doing. I watch him training and look at his attitude intently. It's a purely sporting decision and nothing to do with a disciplinary act.
"Does Tony still have a future at this club? For me, all I think about is the game against Waasland-Beveren.
"I don't want all the attention being focused on Tony Watt not getting picked. He has many opportunities and we have talked to him. But at a certain point, it stops. You can't keep talking to someone who doesn't want to listen."