Scotland go into their final Group C game needing a result against Carlo Ancelotti's five-time world champions to secure their first ever passage beyond the group stage of a World Cup.
They have accumulated three points from victories over Haiti and draws with Morocco — enough that a narrow defeat could still see them progress as one of the eight best third-placed nations. Robertson made clear, however, that the squad are interested only in the positive result.
The Scotland captain, who will win his 97th cap, has been well-placed to assess Alisson after spending eight years alongside him at Liverpool.
"He's the best keeper in the world," Robertson said. "I've been very lucky to play with Ali for the last eight years. In big moments, he was always there for us. Even when our defence was at its best, sometimes the other team would get through.
"But we could always rely on Ali to go and make the saves. He's an unbelievable goalkeeper and even better person. He's someone I admire so much, him and his family. I'm lucky to be close to them because they're fantastic people. But I really hope he's picking the ball out of his net a couple of times on Wednesday — more than I'm used to!
"I can't speak highly enough of him as a player and as a man. But let's hope against us he doesn't keep a clean sheet. We have to believe we can score against Brazil. If we don't, there's no point showing up. That's our aim. If we can do that hopefully it can be a big night for our country."
Scotland have not beaten Brazil in 10 attempts stretching back to 1966, with four of those meetings coming at the World Cup. Robertson insisted the squad's focus is only on the result that would create history.
"We're playing against a massive country, the most iconic in the World Cup, obviously most decorated," he said. "But it also gives us an opportunity to achieve our dreams. We want to achieve history for our little country. And then we have an opportunity to do that against Brazil. When it comes to the game, we are in control of our own destiny at the minute. What we know is if we get a result, then they'll be one hundred per cent through. So we have to focus on that."
Scotland go into the game with Robertson, Kenny McLean and Findlay Curtis walking yellow-card tightropes after picking up bookings across the first two matches, while Aaron Hickey misses out through injury. Robertson was untroubled by the suspension risk.
"You have to play the game, that's part of football. You can't start worrying about suspensions or anything that goes along with that. There's a few of us on bookings and it will be the same through the whole tournament going into the last game. The players all have to be 100 per cent and I certainly will be — whether I'm on a booking or not."
Scotland's attacking output has been the primary concern going into the decisive game. They mustered nine shots against Haiti and just six against Morocco, with only two on target in each match.