The Sabbath was not limited to the day we call Saturday. In fact, I am one of those who believes that Jesus was crucifierd in a year when the first day of Passover fell on Friday. That made it a special Sabbath day, with all the restrictions that the regular Sabbath contained.
The Last Supper took place on Wednesday evening as we measure it today. He was arrested later that same evening, taken to the home of Caiaphas, and held there until 6:00 AM the following morning, which would be what we call Thursday morning.
Jesus was then taken to Pontius Pilate, who went through the motions of wanting to spare him while actually orchestrating his death. He was scourged and taken to Golgotha, where he was crucified at about 9:00 AM Thursday morning. He lived until 3:00 PM that afternoon, when he announced that his work was done, and then died.
Now Joseph of Arimathea was racing against the clock. Jesus was dead, and he wanted to get permission of Pilate to take his body and entomb it. but since the following day (Friday) was the first day of Passover, he had only until 6:00 PM to accomplish this and then arrive home in time so as not to violate the special Sabbath directive. He purchased the cloth in which to place Jesus' body, hurried back to Golgotha with Pilate's premission more than likely written as a note, had helpers take Jesus' body down from the cross and take it to his nearby tomb, had them roll the stone in front of the tomb's entrance, and then made it home by sundown.
It was in this way that Jesus' prophecy concerning himself was accurate. He was entombed for Thursday night, Friday night, and Saturday night as we measure the days, as well as being in the tomb for part of Thursday (which would still count as a day irregardless of the length of time), Friday and Saturday.
Where we Christians get the day wrong is due to 'tunnel vision'. We hear the word 'Sabbath' and automatically assume that it means Saturday. But a Sabbath day according to Mosaic Law also describes the first and the seventh day of Passover, irregardless of when those days fall in the week. In the year in which Jesus suffered his passion and death, that day was Friday (Leviticus 23:5-8).