Sigurdsson is happiest operating in central role behind a striker.
But the presence of Wilfried Bony and Bafetimbi Gomis up front at Reading last weekend meant the Iceland star started on the right flank.
And though Monk is aware that Sigurdsson prefers to play down the middle, he says Swansea's summer recruit from Spurs must be prepared to be versatile.
"No. 10 is probably Gylfi's strongest position, but a footballer nowadays should be able to play anywhere," said the Swansea manager.
"I said that to him on day one. Good players can play anywhere and Gylfi is a good player.
"It's about adapting to what's required in those different positions. Within games you end up in different positions anyway. It's a question of understanding what's required from you when that happens.
"Of course, Gylfi I am sure would say himself that he prefers the No. 10 role and we know that, but I would be stupid not to experiment with other ways of doing things."
Swansea looked impressive going forward at Reading, with Sigurdsson coming off the right wing and Wayne Routledge impressing on the left while Gomis and Bony led the attack.
But Monk indicated afterwards that Swansea will usually use the 4-2-3-1 system which has served them so well in recent years.
It could be therefore, that Sigurdsson slots into his favoured role when Swansea take on Villarreal in their final pre-season friendly tomorrow.
The former Liberty loanee looks set to be a key figure this season — and Monk believes Sigurdsson's return to Swansea will give him the chance to blossom.
"He is a quality player who has come back a better player than when he left," he added.
"He had a difficult time at Tottenham and probably didn't play as regularly as he would have wanted, but obviously there was a lot of competition for the places in the team he was vying for.
"I spoke to him about it. I felt that every time he did play at Spurs he felt that because his chances were limited, he had to prove something or score a goal.
"For me I have told him to come here and settle himself.
"It's about him being a proper player now for the duration of the time that he is here.
"It's about learning not just to be an attacking midfielder, but an all-round midfielder as well.
"If he does that, because of the quality he has he will get his chance to go to the top again, because for me he is a top-six player with ease.
"He could easily play in any of the big leagues in Europe but I think he just needs to establish himself a bit more as an all-rounder.
"We will work with him on that and that will benefit us massively, but obviously benefit him as well."
Sigurdsson will this weekend make his first home appearance for Swansea since the 1-0 win over Liverpool in May 2012.
And he is relishing the prospect of running out in SA1 again.
"It's been a while since I've played at the Liberty in a Swansea shirt, so I'm really looking forward to Saturday," he said.
"I obviously enjoyed my loan spell at the club and I've fond memories from my games at the Liberty.
"I remember the supporters were always singing and getting behind the players, and that's so important for us a club."