The 24-year-old Sen already gave evidence that he is in the shape of his life when he beat the Chinese World No.1, Shi Yuqi, in the first round of the tournament.
Despite battling painful blisters on his foot and severe cramps in the game against Lai, Sen showed an incredible will to keep fighting against the 21-year-old Lai, who had claimed a surprise bronze medal at last year's World Championships in Paris.
Momentum often shifted in favor of both players in the gruelling contest which lasted one hour and 37 minutes.
Its the second time that Lakshya Sen manages to make it all the way to the All England final after finishing runner-up at the 2022 edition.
The 24-year old will now chase history when he takes on world No. 11 Lin Chun-yi of Chinese Taipei in the summit clash on Sunday.