The Nikkei ended the day down 1.71 point at 37,722.40, effectively unchanged but snapping a three-day rally.
The broader Topix also finished essentially flat but up 0.02 point at 2,769.51.
Japanese stocks were initially buoyed by a sharply weaker yen, which boosts the value of overseas revenues for the country’s many heavyweight exporters.
However, a poor auction of super-long Japanese government bonds also saw yields pushing higher again, weighing on sentiment.
The Nikkei particularly struggled above the key psychological level of 38,000, after pushing as high as 38,178.73 in morning trading. Some additional push is needed to take the Nikkei firmly above 38,000, such as further positive developments in U.S. tariff negotiations, said Masahiro Ichikawa, chief market strategist at Sumitomo Mitsui DS Asset Management. While a weaker yen supports sentiment, “one can’t say the foreign-exchange market has stabilized”, he added.
Despite the more cautious finish to the session, chip-testing equipment maker and Nvidia supplier Advantest remained the Nikkei’s biggest gainer in index-point terms through to the close, ending with a 1.6% advance.
By contrast, chip-making machinery manufacturer Tokyo Electron flipped from early gains to finish down 0.1%.
Automakers as a group had been strong in early trading but ended the day mixed. Honda climbed 1.3%, but Toyota reversed gains to drop 0.3%.
Nissan was among the most volatile stocks on the day, leaping as much as 4.6% at the start of the afternoon session following a media report that it plans more than $7 billion in fundraising to help turn the business around. However, it shed those gains to end the day down 0.3%.