In the first semi-final game, Alkaras beat Serb Novak Djokovic (ATP 7) with 6-4, 7-6 (7: 4), 6-2, denying him a fight for the 25th Grand Slam title in his career.
Djokovic made it to the semi -finals of the entire four Grand Slam this season, but he reached the finals.
Sinner, with a 6-1, 3-6, 6-3, 6-4 outscored Canadian Felix Ogie-Aliasim (ATP 27).
Alkaras and Sinners are the first to compete in three finals in the Grand Slam men’s tournaments in one season. Alkaras was superior in France and Sinner in Wimbledon.
Last year, Italian Jannik Sinner became the US Open champion, beating American Taylor Fritz in the final with 6-3, 6-4, 7-5.