Ange Postecoglou said Tottenham are undecided whether to take up their option to sign Timo Werner after the winger's season was ended early due to injury.

Werner sustained a hamstring problem in Sunday's 3-2 home defeat to Arsenal and although he will not play again, sources have told ESPN the 28-year-old is expected to undergo further rehabilitation at Spurs rather than return immediately to his parent club, Red Bull Leipzig.

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Tottenham brought Werner to north London in January as part of a loan agreement which included an option to buy for a fee in the region of 15 million. He has registered two goals and three assists from 14 appearances, and although Postecoglou hailed Werner's positive impact at Spurs, the Australian insisted no final decision would be taken until after the season was over.

"The only reason for that is that it's not about the here and now, it's about the overall strategy," Postecoglou said. "I'm talking about where I want us to be [in the] next six months to be in a better place than today. Timo we signed until the end of the season on loan and he's part of that strategy to see what we need to do in the summer and can we do it.

"Are there going to be other gaps and where does Timo fit in with that strategy? So we have a plan in place, and that was irrespective. I think he's been very good for us. He came in at a really important time in January when Sonny [Son Heung-Min] was away [at the Asian Cup] , then Richy [Richarlison] got an injury.

"We were short in wide areas. Him coming in was very helpful for us and I think he's made an impact but in my mind to make those definitive decisions, I still need some clarity about what we've got here first."

Postecoglou has faced more criticism for Tottenham's set-piece defending after conceding twice from corners against Arsenal.

The 58-year-old has never employed a set-piece specialist coach in his career and Spurs have conceded 12 Premier League goals this season from dead-ball situations. Only five teams have a worse record.

Asked if he was bothered by that scrutiny, Postecoglou quoted Billy Joel song "You May Be Right" in response.

"Not in the least. I get it. It's not an answer [people want]. To quote Billy Joel, 'you may be right, I may be crazy, but it's maybe a lunatic you're looking for,'" Postecoglou said.

"I'm just not interested in it. I never have been. Enough of you have done enough research on me to know this is not the first time I've been questioned about set pieces in my coaching career.

"There is an underlying reason for that which I'm very, very comfortable with."

Asked to elaborate on that reason, Postecoglou said: "No. Do a bit of work, mate. Come on."

Ben Davies has also been ruled out until next season with a calf problem, meaning Emerson Royal is likely to deputise at left-back in Thursday's trip to Chelsea.