Ireland were denied an obvious goal that would have won them the game against Portugal, according to their manager Stephen Kenny.
Portugal held Republic of Ireland to a goalless draw in the Aviva on Thursday night, as the hosts looked to control the game for much of the second half.
While Cristiano Ronaldo was kept out a few times by Gavin Bazunu in goals, it was a chance from Matt Doherty that could have been the winner for Ireland, had the referee not blown the whistle for a foul by Will Keane.
Speaking on RTE after the match, Kenny voiced his frustrations at the decision.
"Just looking back there, it is clearly not a foul," Kenny said. "Will Keane stands his ground. The goalkeeper is actually the proactive one.
"He is actually any barging that is being done. So, it is a clear goal that has been disallowed. It is very disappointing that it has not been given, because it looks like a clear goal.
"We couldn't get a decision in the first half at all," Kenny added. "Everything seemed to go one way. I think the players kept their composure.
"We didn't get any key players booked ahead of the game on Sunday which is important. But we passed the ball very well and out front three improved as the game went on and we are disappointed not to win."
Ireland's performance was promising for Kenny
In spite of the disappointment from the loss, Kenny believes that the two matches against Portugal show promising signs for the national side.
"We've played Portugal twice," Kenny said. "We played them in Portugal and in the 88th minute we were one up. We have drawn today at home.
"The players are very disappointed with that. That shows you the strives we have made in recent months. I think the draw was important; that draw means we can finish ahead of Luxembourg if we win, which we want to do."
It was particularly in the second half that Kenny saw the Irish take control.
"I thought we started nervously; they were good early on in terms of possession," Kenny said. "In the last 20 minutes of the first half, I think we really caused them problems.
"We had a lot of corner kicks and Chiedozie [Ogbene] was causing a lot of problems with his pace for a good spell. We had a lot of good football, and in the second half I thought we were the better team.
"They are always a threat; they have so much quality as we have seen with the chance that they had."
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