The Uruguayan has inherited the Black Cats reins from Paolo Di Canio and been charged with the task of turning their season around.
If he was not aware of the size of the challenge facing him at the Stadium of Light, a 4-0 reversal at Swansea City in his first game in charge has offered a rude awakening.
Things are not about to get any easier for a side that has collected just one point from eight matches, with their next outing a Wear-Tyne derby against Newcastle United.
Poyet is reluctant to bill that contest as a must-win, but appreciates that Sunderland need to find a spark from somewhere if they are to start piecing together a survival push.
He said: "On one side, we have time. But I don't want to go to the other side and say this game is a final.
"But at the end of the day, it's about winning a football game, and it needs to be now.
"We say in Spain, 'Yesterday and not even tomorrow. Now'. So then we go from there.
"It's a great opportunity. Can we do it? I believe we can, and we are going to work so hard this week to make sure that it is possible."
Poyet insists he took the Sunderland job with his eyes open, but has urged supporters to be patient as there is no quick fix.
"I knew what the task was. I know, with my knowledge, what we need to work on," he said.
"But I don't know how quickly it will work. I can't tell people it will work in five days or a month. I hope it works really quickly. We cannot lose many more times.
"From my side it's great to have a long week before playing Newcastle. Monday to Saturday with the game on the Sunday gives me enough time to work on the pitch with the players, every day."