Raheem Sterling set up Kane to double England's lead in the 39th before Alex Iwobi reduced the deficit in the opening two minutes of the second half.
Nigeria: Francis Uzoho: 7; Bryan Idowu: 6; William Troost-Ekong: 6; Leon Balogun: 6; Odion Ighalo: 5; John Obi Mikel: 6; Victor Moses: 7; Shehu Abdullahi: 6; Joel Obi: 6; Ogenyi Onazi: 6; Alex Iwobi: 7.
Mikel knows Nigeria have to sharpen up in Russian Federation if they to get through a tough group featuring Argentina, Iceland and Croatia.
But the Nigeria boss blamed their slow start on fatigue caused by a hard journey to England and rain that stopped them training the day before the match.
Summarising the match, Southgate said: "Firstly, yes, really pleased with the first half".
"We couldn't train on Friday because of rain, the pitch wasn't good".
"The team we picked today, my experience of the weeks leading into a tournament and then the first couple of games of the tournament - is that it will evolve because of different things". We arrived after a 10 hour flight, with many stops.
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That's especially important as Apple is preparing another big push for the wearable hardware later this year. This past April, however, Apple poached John Giannandrea from Google where he was head of search and AI.
England relied on goals from Gary Cahill and Harry Kane before slackening in the second half to beat Nigeria 2-1 in a World Cup warmup match on Saturday.
Kane scored England's second goal with a fine finish and linked play with confidence in the final third. It was much better.
The goalkeeper, who has recovered from a hairline fracture in his left foot, played the entire match but couldn't prevent the world champions from losing for the second straight game after a 1-0 defeat to Brazil in March.
Only three players have scored in four World Cups - Brazilian great Pele and German strikers Uwe Seeler and Miroslav Klose.
The Chelsea defender, who was in and out of the Blues' team during the 2017/18 season, rose highest to meet a Kieran Trippier cross, heading into the top right corner to reward England's bright start.
"I heard the coach of the England team say they want to win the World Cup in 2022, so we can say the same (of our youthful team)". "That was as good a half as we've had I think". We didn't always find them, didn't always see them, but there was a lot of unselfish one and two-touch play and that really pleased me.