who is the first Achaean warrior Athena aids in battle?

The first Achaean warrior that Athena aids in battle is Diomedes. In Homer's "Iliad," she inspires him during the Trojan War, granting him exceptional courage and skill. This divine assistance allows Diomedes to perform remarkable feats, including wounding the Trojan prince Aeneas and even confronting the goddess Aphrodite.