Thiago Agustín Tirante (born 10 April 2001) is an Argentine professional tennis player who achieved a career-high ATP singles ranking of world No. 50 in August 2026. As a junior, he captured the 2019 French Open boys' doubles title with Matheus Pucinelli de Almeida, won the prestigious Orange Bowl singles trophy, and was named the 2019 ITF World Junior Champion.

After making his ATP Tour debut at the 2021 Argentina Open and winning his maiden Challenger title that year, Tirante broke through at the 2023 French Open with his first Grand Slam win over Botic van de Zandschulp. His momentum continued in 2024 when he reached his first ATP semifinal at the Swedish Open, upsetting top-10 star Andrey Rublev, and cracked the top 100 for the first time. Following a strong 2025 season with several Challenger titles and a Masters 1000 debut in Miami, he enjoyed a remarkable 2026 featuring three top-10 wins, a Masters 1000 quarterfinal appearance, and his rise into the world's top 50.