Cape Town - When Springbok coach Rassie Erasmus names his side for Saturday's clash against England at Twickenham on Thursday, Damian Willemse will be handed a first Test start. 

Still just 20-years-old, the highly-rated Stormers and Western Province playmaker will wear the No 15 jersey in front of what is expected to be a crowd of around 80 000. 

It will, without any doubt, be the biggest day of Willemse's short career to date. 

Willie le Roux has made the position his own in 2018 and, barring injury, will be South Africa's fullback at next year's Rugby World Cup in Japan. 

Willemse, though, is currently seen as Erasmus' second choice and he already has one foot on the plane to Japan himself. 

Erasmus said in Stellenbosch last week that, if he continues to play well, Willemse has a "very good chance" of making the World Cup squad. 

A solid performance on Saturday on a stage as big as it gets would go a long way. 

It hasn't taken long for Willemse to earn an almost cult-like following in South Africa, particularly in the Western Cape. 

The hype is understandable. 

In a short space of time, and particularly during this year's Super Rugby campaign when he was given the freedom to lead the Stormers at flyhalf, Willemse showed a promise that suggested his future would be as bright as anybody's. 

His natural side-stepping ability immediately stood out and, combined with his burst of pace from a standing start, it made him a real danger with ball in hand. 

Willemse's enterprising distribution was also noticeable during that Super Rugby season, while the distance he generates from the boot is impressive for such a youngster. 

The ingredients are all there, and as a result, there are many who believe Willemse's best position is flyhalf. 

Western Province coach John Dobson, for example, believes that Willemse is one of the best No 10s in the country.

Erasmus, meanwhile, has made it clear that Willemse's immediate, short-term future with the Boks is at fullback. 

Handre Pollard and Elton Jantjies have the flyhalf berth covered, and Erasmus is not prepared to back a player with so little experience in such a key position at a World Cup. 

Playing at fullback, however, comes with a different set of expectations. 

On Saturday, Willemse must show that he is more than simply fleet-footed.

As the last line of defence against an English side at home, he will be expected to take everything in the air while making all of his tackles. 

His exits will also be under scrutiny. It doesn't help having a big boot if you are not accurate, and Willemse must show that he has what it takes to bail the Boks out trouble when they are on the ropes. 

His ability to join the line on attack is not a concern; Erasmus and everybody else knows that he can do that naturally. 

It is rather in the more mechanical elements of the game where Willemse must shine. He needs to do the basics well, and very few of the basics require flash. 

It doesn't get much bigger than a Twickenham Test, and if Willemse wants to show that he is ready to make the step up onto the international stage, then he could not ask for a better opportunity. 

Kick-off on Saturday is at 17:00 (SA time).

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