Here are the most notable stats from Thiem's first Grand Slam title.
Thiem is now the fifth man since the Open Era began in 1968 to come back from two sets down in a major final. He joins Gaston Gaudio (d. Guillermo Coria, 2004 French Open), Andre Agassi (d. Andrei Medvedev, 1999 French Open), Ivan Lendl (d. John McEnroe, 1984 French Open) and Bjorn Borg (d. Manual Orantes, 1974 French Open).
In a US Open final, Thiem becomes the first man to come back from two sets down since 1949, when Pancho Gonzalez did the same against Ted Schroeder.
Thiem, 27, is also the first man born in the 1990s to win a Grand Slam title. On the women's side, players born in the 1990s or later have combined to win 15 majors, including one by a woman born in the 2000s (Bianca Andreescu, 2019 US Open).
This is the first time in men's tennis that four consecutive Grand Slam finals have gone to five sets (2019 Wimbledon, 2019 US Open, 2020 Australian Open and 2020 US Open). Before this, there had only been two instances of three straight men's major finals going to five sets (in 1927 and 1946).
Thiem is now the second Austrian player, male or female, to win a Grand Slam singles title, after Thomas Muster won the 1995 French Open. Thiem is the only Austrian to make multiple major finals, in which his win-loss record now stands at 1-3.
This was just the second men's Grand Slam final to feature a deciding-set tiebreaker, after the 2019 Wimbledon final between Roger Federer and Novak Djokovic. Last year was the first time Wimbledon began playing a tiebreaker once the set got to 12-12.
The timespan since the last time there was a first-time men's Grand Slam champion (Marin Cilic, 2014 US Open). It is the longest span between first-time major winners on the men's side in the Open Era. The previous longest was almost exactly three years between Juan Martin del Potro (2009 US Open) and Andy Murray (2012 US Open).
Zverev's ace count for the tournament. It's the fourth most in a single US Open since aces were first tracked in 1991. Only Pete Sampras (144 in 2002, 141 in 1995) and John Isner (138 in 2018) have more.
Zverev no longer has an unbeaten record when winning the first two sets in a Grand Slam match. His win-loss record in such situations now stands at 24-1.
Zverev is the first player to come back from two sets down and blow a two-set lead at the same US Open since Todd Martin in 1993. Martin rallied from 2-0 down to beat Jordi Burillo in the first round and then blew a 2-0 lead in the third round against Richard Krajicek.
(Stats courtesy: ESPN Statistics & Information Group)