On 29 May, she sortied from Pearl Harbor, bound for Eniwetok Atoll, where she acted as the flagship of Task Group 52.14, which was assigned to support the upcoming Mariana and Palau Islands campaign. En route, two of her Wildcats were lost, and another was slightly damaged, through accidents. She began combat operations on 11 June, some west of Saipan, providing aerial reconnaissance, close air support, and antisubmarine patrols in support of the Battle of Saipan. On 15 June, at 17:15 in the late afternoon, the officers of "Fanshaw Bay" received a report of five Japanese aircraft proceeding towards her task group to her southwest. Fighters were scrambled, and the aircraft were intercepted away, harrying them as they quickly proceeded towards the carriers. Four of them were shot down, although a fifth aircraft was able to drop a torpedo aimed at "Fanshaw Bay" at 18:12. Fortunately for the carrier, the Japanese plane approaching from the starboard bow, perhaps disrupted by the anti-aircraft fire, dropped its torpedo at a slight turn. Therefore, "Fanshaw Bay" engaged in a hard right turn, easily dodging the torpedo. The Japanese aircraft was subsequently shot down at 18:15.