Keane is battling a knee problem while Dunne has missed several days' training this week with a muscle injury.
However, both were expected to take part in a training session at the Yerevan Republican Stadium on Thursday evening and be available for Friday's game.
Dunne will line up in a back four alongside Sean St Ledger with John O'Shea and Kevin Kilbane as the full-backs, while the midfield will comprise Liam Lawrence, Paul Green, Glenn Whelan and Aiden McGeady.
Keane, who will win his 101st senior international cap, will partner Kevin Doyle in attack.
The Republic know a win tomorrow would send them into Tuesday night's clash with Andorra in Dublin with an excellent chance to open their account with maximum points.
However, Giovanni Trapattoni will adopt the same approach as he has done throughout his reign - playing first and foremost not to lose.
Asked if he would settle for a 1-0 victory tomorrow, he said: "Sure. Immediately.
"We have to play as we have played in games in the past. It is important that we recognise when we can play and when we cannot. The most important thing is the result."
Trapattoni's pragmatism may infuriate his critics, but he can point to the positive results which took his team to within a hair's breadth of the World Cup finals.
It is a theme he revisits regularly whenever he is asked if Ireland could play a more expansive game.
He said: "Brazil and Argentina played beautiful football at the World Cup. They went home."
At 71, ambition still burns bright for Trapattoni as he attempts to guide the Republic to the finals of a major tournament for the first time since 2002.
Their current group is a tough one, with Russia, Slovakia and Macedonia their most likely challengers.
Asked if they could go one better than they did in the last campaign, which saw them finish second behind reigning world champions Italy, Trapattoni replied: "I have been a manager for 30 years and I have never said 'I am sure'. But in my heart, I feel maybe we can win it.
"But it is not an easy group - Slovakia, Russia, Ireland..."
As the expectant Armenian media waited, Trapattoni added: "Armenia", although more out of respect than expectation.
Even the most patriotic Armenians will admit Vardan Minasyan's men will have their work cut out to have a major impact on the group.
However, Ireland made something of a name for themselves as they pushed Italy close and then gave France the fright of their lives last time around, and Trapattoni is looking for exactly the same level of performance.
He said: "In the last qualifying campaign, we were unbeaten, and we have to have that same mentality.
"We have to think about our opponents, but the team knows this is our way.
"The first thing, although we always want to play well when possible, is the result. Afterwards, we will think about whether we played well or not.
"We have to play for the result. I don't know whether tomorrow's game will be good or not good, but it is the result that is important."
Kick-off is at 4pm.