The day was Friday. However, one should note that based on the Jewish Calendar, their days began at sunset. Therefore, Nisan 14 33 CE began on Thursday evening at sunset and ended Friday Evening at sunset.
"From the sixth hour on, a darkness fell over all the land until the ninth hour. About the ninth hour, Jesus called out with a loud voice, saying: “Eʹli, Eʹli, laʹma sa·bach·thaʹni?” that is, “My God, my God, why have you forsaken me?" (Matthew 27:45-46) The sixth hour would be 12:00 noon and the ninth hour would be 3:00 in the afternoon on Friday. Since the Jewish Sabbath began at sunset on Friday evenings, Jesus' burial was expedited. No work was to be done once the Sabbath began.