Eamon Dunphy lamented a "sadness" that the Republic of Ireland hadn't "given it their best shot" against Belgium - but insisted victory against Italy and progression to the last 16 is still within reach.

Romelu Lukaku's brace and an Axel Witsel header cut apart an Irish side outclassed in Bordeaux, and left their hopes of remaining in Euro 2016 beyond the group stages hanging by a thread. 

They will almost definitley need to defeat the Azzurri in Lille next Wednesday to escape as one of the best third-placed teams, but Dunphy warned Martin O'Neill's men need a change in mentality and approach.

"This is us reverting to sterile, long-ball, negative sideways passing, as opposed to the two games against Bosnia and the game against Sweden where we got the ball and strung passes together," RTÉ soccer analyst Dunphy said after the defeat.

"In our own minds, the opposition were too formidable for us."

"There were wrong choices by the coach. He stuck by [James] McCarthy through thick and thin. [Ciarán] Clark he had options with.

"The option of playing [Richard] Keogh, who did well in the qualifying games. The option of playing the young lad from Blackburn, Shane Duffy.

"There's no mystery about it. There's just a sadness about it really; that you feel you haven't given it your best shot. But we have got a chance against Italy to redeem ourselves. We have a chance against a weakened Italian team to win the game, get four points and go on."

Ireland switched off at key junctures of the game as the classy Belgians danced their way through flailing white bodies.

Dunphy believes O'Neill got his team wrong at Stade de Bordeaux, singling out midfielder McCarthy and Clark at centre-half for particular criticism, and said Ireland were beaten before kick-off as they cowed to the star-studded opposition.

"This is a team without belief and, in the end, without shape," he added. "James McCarthy, we tried to praise him at half-time for putting pressure on the ball, but there's no escaping the fact he was culpable for two of the goals, and Clark was also culpable.

"Clark could have given three own goals away against Sweden. That's the coach's choice, McCarthy is the coach's choice. Choices were made, options were ignored and we were punished severely. 

"In midfield you've got to have a desire to have the ball, to be on the ball. Against Sweden, Jeff Hendrick really showed that in spades.

"Young Brady was knocking git in to them, going to get the next ball. Wes [Hoolahan] came deeper. We had the ball, we made the Swedish work, and we created danger. That was absent today. Why? Because in our own minds, the opposition were too formidable for us."