Malaysia's Lee was put through his paces by Vietnam's Nguyen Tien Minh, and he had the net cord to thank as he edged a tight deciding game and took it 21-23, 21-16, 21-17.
"Today I didn't play so well," Lee said after the gruelling match which saw the sweat-drenched players changing their shirts and frequently towelling their faces.
"The first game was point for point -- I just tried in the second game. The two players (both of us) were very tired so I tried to become very fast in that second game."
Long-time number one Lee has frequently been undone by Lin on the big stage and the 31-year-old is now making his last attempt at winning Asian Games gold.
"Before I went out on court I heard Lee Chong Wei had told Chinese reporters that he had nothing to lose in a match against me," said Lin.
"This is the same for me. I will go all-out."
Nguyen, 30, fended off a barrage of Lee smashes as he took the first game, forcing the Malaysian star into a change of tactics.
