The 35-year-old South African was carried off on a stretcher after extended treatment on the pitch 18 minutes into the game at Molineux. And Elland Road boss Kevin Blackwell gave a frank assessment of his latest injury.
"Lucas went down after 11 minutes and I have to tell you the prognosis is not good," Blackwell confirmed.
"The initial indication is that Lucas has suffered a rupture of the Achilles' tendon and if that's true it means he's probably played his last game for Leeds United because he only had this year left on his contract.
"He's gone to hospital for more tests but it doesn't look good and it's such a shame because this is his testimonial year.
"Lucas was moving forward to play the ball and he felt what he thought was a kick and that's usually the tell-tale sign of the tendon snapping.
"That's why we fear the worst."