Ireland boss Giovanni Trapattoni declared the match against Russia the moment when their Euro 2012 campaign really kicks into gear.
Eire already have six points on the board courtesy of wins over Armenia and Andorra but Friday's clash in Dublin and Tuesday's trip to Slovakia should go a long way to determining whether they can reach a major finals for the first time in a decade.
Trapattoni said: "We should be optimistic about claiming four points (from the two games), which would allow us to stay at the top of the table. The way the qualification works, it's very long and Friday is the start of the more important phase. We will play against one of the most famous international teams."
He added: "Most of their players play every week for the same teams, Zenit St Petersburg and CSKA Moscow, and that is a great advantage.
"But I have reasons to be positive because we are building a very good team. We are happy with our mentality and how our players play the game. We can play well but more important is the result."
After losing Damien Duff to a calf injury earlier this week, Trapattoni was able to report good news on that front today with Richard Dunne returning to training following a knee problem.
And the Italian duly named the centre-back in an unchanged starting line-up from the win over Andorra.
"Richard trained this morning and hopefully he will be okay, and that is good news for us," added Trapattoni.
Dunne's importance to the side was stressed by captain Robbie Keane, who said: "Richard is one of our key players and he's been instrumental in the 10 years he's been involved in the Irish side. He's grown and grown and become an absolutely vital player."