Andrew Omobamidele has been omitted from the Republic of Ireland squad for tonight's World Cup qualifier against Portugal at the Aviva Stadium.

Speaking to the media on Wednesday evening, manager Stephen Kenny was not optimistic about the Norwich defender's participation due to an Achilles injury.

Omobamidele broke into the Ireland side in the away game in Portugal in September following a first-half injury to Dara O'Shea. And the young Dubliner has barely put a foot wrong throughout the last three games, where he has started in the centre of defence.

Kenny will have to make changes from the now established trio, which also includes Shane Duffy and John Egan.

Jayson Molumby has also picked up an injury and the manager confirmed that the County Waterford native will not be in contention to play against Portugal.

"Andrew Omobamidele has a fitness check as he got a kick on his Achilles in the Norwich game at the weekend," said Kenny, speaking at the pre-match press conference.

"It’s a bit sore so we’ll have to see how he is. We’ll have to wait and see. I can’t say I’m optimistic.

"And Jayson Molumby has tweaked his hamstring and is not available for tomorrow night."

It's not looking for for Andrew Omobamidele, who is nursing an injury

Kenny has options to use Seamus Coleman or Matt Doherty in the three-man defensive unit, which has now become a definitive part of the manager’s preferred formation, as both have slotted into the role in previous games, however, Nathan Collins is another option to consider.

"Nathan has done very well and is certainly in contention," said Kenny.

"It’s an area where we have three emerging players in that position and it’s great for the future with Dara O’Shea, who got injured, and Andrew Omobamidele who has been brilliant so far and has looked so natural, which is great to see."

Portugal come to Dublin with a string of world class players, not to mention talisman Cristiano Ronaldo, who broke Irish hearts with a late brace in the return game last September.

However, the Ireland manager believes his side are continuing to improve and is excited to get a chance to play in front of a full house against the star-studded outfit.

"We are at home, we have a lot of good players ourselves, and we are evolving as a team, you see the progression of the team, and see the team evolving in front of your eyes every game we play. And you see the improvement, so we’re excited about the game," said Kenny.

"It is 14 months since my first match and we had a year of empty stadiums.

"It was a bit soulless when it’s empty like that, and when you go to 25,000, it’s such a difference, and 52,000 for this game, it’s amazing.

"It’s the first game since restrictions were lifted. We are very enthused by that, excited by that, and the players are motivated by that and they deserve to feel the affection of the support as they have been showing their talent over the past couple of windows.

"And the connection between the team and the supporters and we want to see that continue to grow."

Follow the Republic of Ireland v Portugal via our liveblog on RTÉ.ie/sport and the RTÉ News app, watch live on RTÉ 2 and the RTÉ Player, or listen to live radio commentary on 2fm's Game On.