2016 All-England Championship: Lin Dan eyes sixth title after beating Xue Song in semis
Fifth-seeded Lin came from a game down for the third match in succession to beat younger compatriot Xue 18-21 21-15 21-9.
“In the last few matches I have made mistakes but I was really pleased how I came back,” said 32-year-old Lin, who last reached the All-England final in 2012.
“My winter training has really improved things and it has given me plenty of physical reserves.”
His fitness was evident in a truncated encounter, with Lin happy to keep rallies alive and rarely going for attacking winners.
The balance shifted when Lin directed a smash at Xue’s body in the second game, which seemed to resurrect the double Olympic champion.
Xue, the 22-year-old who ousted holder Chen Long in the last 16, was forced to stop for cramp in the decider, before Lin raced to the finish line after 88 minutes.
“Mentally I was a little bit soft today,” said Xue.
Lin will play either Tian Houwei of China or Denmark’s Hans-Kristian Vittinghus in the final, who are due on court in Saturday's final match.
Should Lin triumph, he will join Ireland's Frank Devlin, Denmark's Erland Kops and Indonesia's Rudy Hartono as the only players with six or more titles.
In the women’s singles, Wang Shixian, who won the first of her two titles in 2011, overcame Tai Tzu Ying of Taiwan 21-23 21-12 21-15 to reach her first All-England final for two years.
Shixian had a 6-2 winning record over her opponent prior to their semi-final, but Ying sensed an upset when she produced a delightful backhand drop to take the opener.
Shixian, however, rallied to create pivotal openings in the next two games before criticising her performance, as well as the match officials, following her 71-minute victory.
“I’m really not happy with the performance, something went wrong with my tactics today,” Shixian said.
She went on to criticise the English umpire and line judge and, despite her opponent Ying heralding from Taiwan, Shixian added that she "wished the umpires could be fair to the Asian players".
Shixian will meet either holder Carolina Marin of Spain or Japan’s Superseries champion, Nozomi Okuhara, in Sunday’s final.