The 19-year-old, who retained his individual title in Japan last month with a world record score, nailed three quadruple jumps, including a graceful quad toe-loop, triple toe-loop combo, pipping countryman Vincent Zhou by less than a point.
Chen posted 199.49 points after watching world bronze medallist Zhou earn 198.50 as the American skaters again underlined their dominance.
Japan’s Shoma Uno took third with 189.46 points but suffered a nasty spill attempting a triple axel, quadruple toe-loop combo, crashing to the ice face first before jumping up wincing in pain.
The United States finished day two leading the standings with 91 points with hosts Japan on 79 and Russia 70, followed by Canada (59), France (54) and Italy (52)
Zhou pumped his fist over and over after skating a personal-best, but Chen’s skate was the more polished — if some way short of the world record 216.02 points he scored in March to crush Japan’s Olympic champion Yuzuru Hanyu.
Earlier, French ice dancers Gabriella Papadakis and Guillaume Cizeron, the four-time world champions, set a world record of 135.82 points to briefly take the wind out of American and Japanese sails.
Chen won a bronze in the team event at last year’s Winter Olympics behind winners Canada, but the Americans have been in a different class since Pyeongchang.
Defending champions Japan have the chance to hit back at the weekend in the women’s free programme with 16-year-old Rika Kihira, the country’s new skating sweetheart, in superb form after winning the short routine in a new world best.
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