Tsitsipas defeated Diaz Acosta 4-6, 6-3, 7-6(8) in the quarter-finals on Friday evening, saying it was "extremely difficult to maintain the same level throughout the match". The Greek player said that at some moments he came close to losing the match and reminded himself that he was wearing a headband with a mountain on it and he had to climb it. “So, it helped me move forward,” Tsitsipas said after the match.

In a thrilling two-hour, 31-minute contest, Tsitsipas had a chance to win the match 5–4 in the third set, but Dia Acosta fought back after two double faults in the game. Argentina then failed to convert match point on the Greek's serve at 5–6, before both players saved match point in the tie-break in the third.There was not much to separate them, it was Tsitsipas who held on to pip Rafa Nadal, saving another match point at 6/7 in the tie-break, before he converted his third chance to win. After his ninth consecutive win, the fifth player collapsed on the court in joy, before rising to his feet to embrace Dia Acosta, who committed two costly double faults in the tie-break. Tsitsipas is chasing his second title of the season, having captured his third Monte-Carlo Masters title last week. He has moved up one place to number 7 in the ATP Live Rankings.

The 25-year-old, a three-time finalist in Barcelona, ​​holds a 28-2 record against players outside the top 20 in the ATP rankings on clay since the start of 2022.He will look to maintain that record when he faces No. 59 Duša Lajovic in the semi-finals on Saturday. Lajovic defeated Frenchman Arthur Phil 6-4, 3-6, 6-2 to reach his eighth tour-level semi-final and just his second since 2020. The world No. 59, a two-time tour-level champion, is the lowest-ranked semi-finalist in Barcelona since world No. 63 Tsitsipas in 2018.