The 2021 French Open runner-up forced an error on Khachanov’s forehand to take an early break, only to surrender his serve immediately.
The pair traded breaks again in the first set, but Tsitsipas came alive in the tiebreak and surged ahead in the match before taking the lead in the second set when Khachanov’s level dropped.
Despite three foot faults and two time violations on serve, Tsitsipas appeared more at ease after winning the second set.
The 24-year-old broke Khachanov in the third set to take a 2-1 lead, but the Russian fought back to tie the match at 5-5 before going to a tiebreak. Tsitsipas drew roars from the crowd with two superb inside-out forehands, but squandered two match points, allowing Khachanov to take the set.
The Greek regrouped in the fourth set to go up 3-0 and finished the match in style to reach his second Grand Slam final.