9 August 1945:

260 miles NE of Aparri. After 0800 Hashimoto sights a zigzagging convoy of ten transports escorted by three destroyers at 7,700 yards (in reality the hunter-killer team Task Group 75.19 led by USS SALAMAUA (CVE-96), carrying out ASW sweeps on the convoy route between Leyte and Okinawa).

Kaiten Nos. 3, 5 and 6 are readied for launch, but No. 3 and No. 6 suffer engine malfunctions. No. 5, piloted by FPO1C Nakai Akira, is launched first from 5,500 yards. After a destroyer from the "convoy" appears to be closing the range, Ens Mizui Yoshio's No. 4 kaiten is also launched.

At 1143, CortDiv 70's USS JOHNNIE HUTCHINS' (DE-360) lookouts report sighting a whale 2,000 yards ahead, but it is soon identified as a midget submarine. LtCdr Hugh M. Godsey orders battle stations and heads towards the submarine. At 1208, a surfaced object resembling a "floating iron boiler" about 45 ft long is sighted. JOHNNIE HUTCHINS engages the target with all guns. Nakai's torpedo passes down her port side at 2 knots, trying to point its bow at the DE.

JOHNNIE HUTCHINS' soundman then reports noises of another "submarine" at 700 yards. Next, a periscope is sighted on the port bow. LtCdr Godsey decides to attack the new target with depth charges while shelling the first one.

At 100 yards a direct hit from a 5-inch stern gun is scored on Nakai's kaiten. It is holed and sinks immediately at 20-20N, 126-57E. Meanwhile Mizui's No. 4 kaiten dives and its wake passes down the starboard side of HUTCHINS. A pattern of Mk. 8 magnetic depth charges is dropped and three explosions are heard, after which the contact is lost. ComCortDiv 70 in USS WILLIAM SEIVERLING (DE-441) orders a scouting line formed of four DEs to search for other submarines in the area.
At 1332, eight miles from the area of the first two contacts, JOHNNIE HUTCHINS' lookouts sight another periscope. A depth-charge attack results in a violent explosion, throwing a 30-feet geyser of water in the air. The concussion is felt on WILLIAM SEIVERLING over a mile away.

Four more DEs join the hunt until 1400 the next day, but no further contacts are made. USS JOHNNIE HUTCHINS is credited with probable destruction of two midget submarines and the possible destruction of a third. Her crew is awarded the Navy Unit Commendation.

I-58 comes to periscope depth after her soundman reports a distant explosion. In Hashimoto's opinion, the previously sighted destroyer has disappeared. He heads northwards to evade the hunt, making radical maneuvers to confuse enemy sonars. After sundown I-58 surfaces to recharge her batteries, but is forced under by an approaching airplane.

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