I am going to try my best to recover well and to be ready to enjoy one of these matches that I want to play against probably my biggest rival and at a later stage of our career. He led 5-3 and served it out, winning on his second match point with a backhand volley.
The 17-time Grand Slam champion is an 11-time champion at the tournament - six more victories than any other player in history.
He appeared to be on the verge of tears on Saturday as he spoke to the media.
He admitted that he sometimes is sad because he feels at a disadvantage against his opponents due to his continued knee issues that force him to limit his practice and playing time before he gathered himself. "With all this stuff, I still where I am today". "But I warmed up this morning and felt that my knee wasn't good enough to compete at the needed level".
The 32-year-old was playing only his second event since reaching the final of the Australian Open; he lost to Nick Kyrgios in the last 16 of the Mexican Open.
"It's always something special to play [Federer] and also something special to compete in a Masters 1000 final", Thiem said after his semifinal match.