He took part in the big offencive against the Soviet Tamsagbulag airfield on June 27, 1939 with the 11th Sentai, part of the 12th Hikodan which also included the 24th Sentai and was reinforced by the 1st Sentai. On that day Kimura claimed to have shot down three I-15s and four I-16s even though he was himself wounded. The 11th Sentai claimed 50 enemy fighter planes shot down and three probables with the loss of only two of their own.
WO Kimura Saburo with his Nakajima Ki-27 (Nate) at the Nomonhan front.
Kimura Saburo passed away on August 8, 1939 claiming a total of 19 victories, succumbing to his injuries after an aerial combat with a number of I-16s .