Switzerland meet pre-tournament favourites Brazil at Stadium 974 on Monday, with both teams looking to build on opening games in Group G.
Xhaka, who has been in superb form for Premier League leaders Arsenal, helped the Swiss secure a narrow win over Cameroon, while Brazil laid down a marker with a 2-0 victory against Serbia.
Midfield star Xhaka does not intend to hold back if he comes up against Arsenal team-mates Gabriel Jesus and Gabriel Martinelli and told the pair before they left for Qatar that he would ‘smash’ them if necessary.
‘We were joking before the World Cup to come here and of course, it is always good if you have team-mates opposite your, but we are professional footballers and for 90 minutes,’ Xhaka said.
‘I told Gabby Martinelli and Gabby Jesus if you are running one against one against our goalkeeper I will smash you!
‘It doesn’t matter that we are playing in the same team. This is the Word Cup. You play for your own team, you play for your own country and you want to win.
‘Of course, they were worried. They know me. If I smash you, it will be very very hard.’
Jesus came on for the final 11 minutes of Brazil’s 2-0 win over Serbia, while fellow Gunners star Martinelli was introduced as an even later substitute.
Both players have been key to helping Arsenal move five points clear at the top of the Premier League, with Jesus enjoying a smooth transition following a £50m move from Manchester City last summer.
On the threat of Jesus, Xhaka added: ‘Of course when you see him every day he makes a big big difference. The guy is unbelievable.
‘First of all he is a lovely person, very humble and the quality he has is unbelievable.
‘Of course, with Man City he was playing and sometimes not playing, you are not in this rhythm, but you can see with us he is making the difference and that is why we are where we are at the moment.
‘Brazil have world class players. Big, big quality, the favourites in the tournament and the favourites in our group but it is one game. Anything can happen.’
Switzerland made a promising start to their World Cup campaign but Xhaka has warned his team-mates that tougher tests await as they prepare to face Brazil and Serbia.
He said: ‘The first game is important. It gives you a lot of confidence. If you see the next two games, they will be more difficult than Cameroon, on paper.
‘We enjoy the three points and now we are focused on Brazil. Of course we will have to be much more careful against Brazil than we were against Cameroon. If you lose the ball against Brazil you pay for it. They have great, great quality.’
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