While cruising to attack the Japanese base at Rabaul, Papua New Guinea, Lexington's radar picks up a Kawanishi Type 97 flying boat shadowing her task force. Two VF-3 Wildcats are scrambled and guided to the enemy aircraft by ship's radar. The commanding officer of VF-3, Lt. Commander Jimmy Thach and his wingman Ensign Edward Sellstrom intercept and shoot down the flying boat, getting Lexington's first "kill" of the war. Another Kawanishi is shot down later by pilots Lt. (JG) Stanley and Ensign Haynes.

Admiral Brown of Task Force 11 decides to cancel the raid on Rabaul, since they have been discovered and the element of surprise is lost, but to continue steaming towards the stronghold in a feint to draw attention away from the Dutch East Indies. By this time, 17 G4M "Betty" bombers are headed for Lexington. They meet up with VF-3's Wildcats at 1639 and a large battle ensues, cumulating in threee Bettys shot down in two minutes. Two more are shot down and one damaged enough to drop out of formation before they drop their bombs; all miss the ship.

As the Wildcats of VF-3 continue to hammer the retreating Japanese aircraft, a damaged Betty tries to crash into the ship but is shot down and crashes just short of the stern. One Wildcat is hit and damaged enough that the pilot has to break contact and bail out (later rescued); another spins into the ocean after a 20mm shell hits the windshield dead on; killing pilot Ens. John Wilson instantly. VF-3 had lost one pilot but had shot down or damanged eight of the nine Betty's of the 2nd Chutai of the Japanese 4th Air Group; one of the wounded bombers was shortly shot down by a VS-2 SBD piloted by the Executive officer, Lieutenant Edward Allen and the ninth, and final Betty was shot down by the executive Officer of VB-2, Lieut Walter Henry, in his SBD-2.

By this time the eight flyable aircraft of the 1st Chutai had drawn near to Lexington. Most of VF-3's wildcats were critically low on fuel and trying to land or off chasing the remnants of the 2nd Chutai; only two fighters are nearby, piloted by Liet. Edward "Butch" O'Hare and Lieut (JG) Marion Dufilho. Starting their attack run at high speed, O'Hare cripples one plane quickly (It does not attack Lexington and later ditches) and shoots down a second on his first pass.

Dufilho's guns jam on his first pass and he pulls clear to give O'Hare unrestricted airspace. On the second pass, his first victim is damaged and falls back, but is later able to rejoin the formation in time to attack Lexington. The second aircraft on his second pass dives out of control after the left engine is shot up and seizes. On his third pass, O'Hare focses on the lead bomber of the Chutai, hoping to destroy their attack on Lexington. His fire destroys the left engine of the Betty, which seizes so violently it rips the entire left nacelle free from the wing.

O'Hare fires on his sixth target, but runs out of ammunition after a few rounds from each gun. By this time the four remaining bombers in formation were over Lexington and had released their bombs. All miss, but strike close by, the nearest only 100 feet away from Lexington's stern. The lead bomber O'Hare had tore the engine from managed to control it's death sprial enough eo come near Lexington in an attempt to crash into her, but misses and crashes off the bow, close enough in that the ship has to quickly change course to avoid running over the wreckage.

Only two Betty's from the 1st Chutai return to base. Four had made it through O'Hare's attack and of these, one was shot down by another VF-3 Wildcat forty miles away from the ship and another had to ditch off Nugava Island after being damaged by Edward Allen of VS-2 in his busy SBD-2. Lexington's air group cost the Japanese Navy fifteen "Betty" bombers and two Mavis flying boats (over 100 pilots and air crew) for the loss of two aircraft and one pilot.