TOKYO, Feb 27 (Reuters) - Japanese government bond prices were mostly steady on Thursday, with the super long zone weakening slightly after the Bank of Japan bought less than usual in those maturities via its regular purchasing operations the previous day.
The yield on 10-year JGBs was flat on the day at 0.585 percent.
The 20-year yield rose a basis point to 1.455 percent.
Market participants expect support returning to the super long zone when index-following investors begin extending the duration of their holdings as they customarily do at the end of each month.
JGB futures moved in a tight range, edging up early to 145.24 in reaction to gains by U.S. Treasuries on Wednesday. The futures stood unchanged at 145.18 in afternoon trading.