At 06:25 on 7 May, TF 17 was south of Rossel Island (). At this time, Fletcher sent Crace's cruiser force, now designated Task Group 17.3 (TG 17.3), to block the Jomard Passage. Fletcher understood that Crace would be operating without air cover since TF 17's carriers would be busy trying to locate and attack the Japanese carriers. Detaching Crace reduced the anti-aircraft defenses for Fletcher's carriers. Nevertheless, Fletcher decided the risk was necessary to ensure the Japanese invasion forces could not slip through to Port Moresby while he engaged the carriers.