The north Londoners announced the arrival of their new striker on Tuesday evening, also confirming that the deal includes a buy option which is believed to be worth around €17million (£14.6m).
Werner has struggled to reignite his career back in Leipzig following two profligate season at Chelsea, starting just twice in the Bundesliga in the first half of the season.
But he is confident he can make a big impact back in the Premier League and says he was blown away by talks with Postecoglou, while he feels his versatility will be a huge asset.
‘First of all, I’m very happy to be here,’ Werner told the club’s official website. ‘I think I have joined a very, very big club. The talk with the manager I think was a really, really good talk.
‘He gave me straight away the feeling that I need to join a club, what I want to feel when I talk to a manager.
‘Also the tactics and the style, how he wants to play, how he lets the team play, for me I thought straight away that it fitted perfectly.’
He continued: ‘The new stadium was something really, really special to play at, straight away I loved it. It was always big, big games to play against Spurs and now I’m happy to be part of the team and the club.
‘It should be even more special to score for the home team and to have the whole crowd behind you when you score is even better. Really looking forward to it.
‘I hope I can be the best player I can be here. I can play every position up front, that’s always good when you have players who can play different positions and change also in the game – I think it makes it even harder to defend for the other teams if they never know who is coming in the positions.
‘I think that’s one of my strengths to be flexible up front, to play every position.’
On returning to English football, he added: ‘When I left the Premier League, straight away I missed something because it’s the best league in the world. I missed London as well, I really settled in well here, I love England.
‘When I left I really missed it because it’s a great city, it’s a great place to be. We’re all happy to be here, to be back, and start a new journey here in north London.
‘My aim is to fight for another win in this league and also maybe for titles. When I joined my old club [Chelsea] I also said I wanted to be a winner and wanted to win titles and in the end we won the Champions League!
‘So I think it should not be a bad thing to say I also come here to win titles and to win something.’
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