Djokovic defeated Berrettini 6-3, 6-2, 6-7 (5), 7-5 in the quarterfinal match, but the Serbian's victory featured an unexpected delay in the fourth set. The match was suspended in the fourth frame for about 20 minutes after an 11 p.m. curfew related to the COVID-19 pandemic was met with resistance and fans had to be ushered out.
Fans were expected to leave the main stadium at 10:45 p.m. due to the curfew. The spectators, however, remained seated, which forced play to be halted. Both Djokovic and Berrettini then packed their bags and walked toward the tunnel as fans jeered and chanted, "We've paid, we'll stay."
Within minutes, the stadium was almost completely empty. The match eventually resumed, and Djokovic closed out the win to set up a showdown with defending French Open champion Rafael Nadal on Friday in the semifinal.
Only Swiss star Roger Federer has more major semifinal appearances (46) in men's tennis history than Djokovic. Djokovic's 11th semifinal berth at Roland Garros ranks second behind only Nadal's total of 14.
The semifinal between Djokovic and Nadal will be the duo's 58th all-time meeting. Djokovic, an 18-time Grand Slam champion, holds a 29-28 edge in their head-to-head series.
Nadal, however, is 7-1 against Djokovic in Paris, including a win in last year's final. The Spaniard has 13 French Open titles compared to just one for Djokovic.
Earlier Wednesday, the third-seeded Nadal defeated No. 10 seed Diego Schwartzman to reach the men's semifinal.