Lamb's form in the early stages of the 1981 season was outstanding and he was selected in the NSW State of Origin side. Lamb was called in at the last moment for a very ill Mick Pattison and only arrived in Brisbane on the day of the match (when Pattison took ill, NSW coach Ted Glossop initially wanted to move Steve Rogers from the centres to five-eighth and play whoever the league gave him as a replacement back from the bench but was overruled by the NSWRL. Lamb, who at the time worked as a linesman for Telecom, was literally found up a telegraph pole and had to make a rushed flight to Brisbane). Lamb met his halves partner, young Parramatta halfback Peter Sterling, for the first time only two hours before kickoff. He made his Origin debut at Lang Park playing opposite another young player on the rise, Queensland captain Wally Lewis who had made his test debut against France only a few weeks earlier. NSW led 15–5 at half time mostly due to the Parramatta connection of Sterling, Ray Price, Michael Cronin and Eric Grothe who picked up a loose Greg Conescu pass to race 90 metres to score in the first half. But the Maroons, led by Lewis and man of the match Chris Close, came back strong in the second half to win 22–15.