Willemse made his name at flyhalf and played in this position for the Stormers during last year’s southern hemisphere showpiece.
But Springbok coach Rassie Erasmus used the talented youngster at fullback for the national team in 2018.
And Erasmus has made no secret of the fact that he wants to play the 20-year-old in this position at next year’s World Cup.
With Willie le Roux being South Africa’s starting fullback and Handre Pollard and Elton Jantjies the two flyhalves, Willemse’s versatility might earn him a spot on the Bok bench for the World Cup in Japan.
But Fleck is still not certain where he will use the youngster in 2019.
And the boss says he will play Willemse where the team needs him in next year’s Super Rugby tournament.
With Jean-luc du Plessis having recovered from the hip injury that ruled him out of action for this year’s Currie Cup campaign and ready for the new season, Fleck says Willemse will have a fight on his hands to get the No.10 jumper.
Currie Cup hero Joshua Stander, who did well in the absence of both Willemse and Du Plessis, is also in the running for the pivot position, while Dillyn Leyds and SP Marais will both look to wear the No.15 jumper for the Stormers.
The back three of Marais, Leyds and Sergeal Petersen were on fire during the Currie Cup season and it is likely that Fleck is considering them as his starting trio.
Of Willemse, Fleck says: “He’s quite keen to give fullback a crack, but the team will come first and whatever position we need him at, we will play him
“We’ll try and help out SA Rugby as much as we can, but it will be ‘Stormers first’, and the players understand that.”