"I hope (it has) given him a lot of belief", Southgate said.
England had started brightly in a blur of passing and movement and could have been two goals up inside the first four minutes.
"Ronaldo is the best in the world, up there with Lionel Messi, but the challenge is there to be with them".
Even though Southgate was keen to focus on the all-round team performance, he did reserve special praise for Harry Maguire, who set up Kane's victor. First Jordan Henderson's lofted first-time pass released Dele Alli and when the ball eventually broke to Jesse Lingard he saw his shot from six yards saved by the outstretched left boot of Mouez Hassen in the Tunisia goal.
As a striker, Harry will have watched Cristiano Ronaldo, Diego Costa and Antoine Griezmann get off the mark in the first few days of the World Cup and would have been desperate to make his impact on the competition too.
Kane said he had not taken advice from Pochettino or England boss Gareth Southgate about how to play in a World Cup. I worked hard to get where I am, I have a lot of determination and I enjoy being here and it is about stepping it up.
Kane has made 25 appearances for his country so far, scoring 15 goals and assisting a further three strikes along the way.
"We understand it's going to have to be a team effort to win the trophy".
Going into the Panama game, England aren't chasing the points.
"If Harry doesn't score we've got players who can", said Tripper.
"But you have to stay calm in them situations and I've had it before, so it wasn't sort of a shock to me, so I knew what I had to do to recover fast enough for the game". But how did the Manchester United stars perform?
Now Southgate's team are in pole position to claim a place in the last 16, as they build towards their second group game, against Panama on Sunday afternoon.
Really pleased to get a win last night.
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