The lone score in Inter's 1-0 win at Genoa came in the 67th minute when Ricky Alvarez's cross was met by Nagatomo just outside of the goal area. It began and ended so quickly that Genoa goalkeeper Sebastian Frey's first reaction was to pick the ball up from the back of the net.
Meanwhile, Nagatomo's reaction was to find captain Javier Zanetti to perform the celebration that has become something of a tradition for the Samurai Blue regular.
"Luckily tonight [Zanetti] was there," Nagatomo told Inter Channel after the match.
"I've been practicing the o-jigi [the traditional Japanese bow] with him."
The bowing celebration came into existence just nine months ago, when Nagatomo scored his first goal for Inter. It was, ironically, the exclamation point in the team's 5-2 home rout of Genoa.
Nagatomo had to finesse his way around Marco Rossi in that March 6 fixture, but on Tuesday night he simply glided ninja-like past an unaware Kakhaber Kaladze for the first heading goal of his career.
"I knew that Alvarez would send me that kind of ball and in fact his pass was marvelous," the attacking defender said in praise of his team-mate.
"What did my team-mates say? They told me it was amazing because I'm small and it was impossible for me to score with my head."
The goal was Nagatomo's second in three days; on Saturday he deflected a poor clearance by a Fiorentina defender and doubled Inter's lead to 2-0.
"I'm really happy because I had never scored two goals in three days. But I'm certainly not stopping here because in the next game I'll score another."
He will get a chance to extend his scoring streak on Sunday against former club Cesena.
"It will be a great thrill because I have ties to both the club and the fans.
"But we'll try to win and, I repeat, I'll do everything possible to score a third goal in a row."
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