Eadie was graded by Manly-Warringah in 1971 and showed immediate promise in the lower grades that season. The following year with the retirement of long serving Manly fullback Bob Batty, he established himself as the team's first grade fullback and his powerful running style was already a serious danger to all Manly's opponents. Though not excessively tall at just under 180 cm (5'10"), Eadie's solid build of around 95 kg (15 stone) gave him abundant pace and so much strength that once he was on the move, few opposing defenders were ever able to stop him when he ran into the backline. At the same time, Eadie was an accurate line kicker and extremely safe under the high ball in an era when the "bomb" was coming into prominence.