Reigning world player of the year Williams has been left behind in the Test team running by rival wings Tommy Bowe and Ugo Monye.

While the Lions’ first Test picks can boast eight tries between them on tour, Williams has not yet broken his duck.

And he is realistic enough to know a Newlands appointment with the Emerging Springboks could leave any future Lions prospects parked permanently in the hard-shoulder.

At 32, Williams appears highly unlikely to be part of another Lions adventure, and an ineffective display tomorrow might well close the book on that particular career chapter.

“It’s my last opportunity, I suppose,” said Wales’ record international try-scorer.

“It is a massive game - it could be my last Lions game ever.

“I need a big game, I know that, to have any chance of playing in the last two Tests. It is all up to me on the day.

“You come on these tours to play in the Test matches, and I want to play more than anything. I am more determined than ever to be involved.”