Chiedozie Ogbene acknowledged it is "all or nothing" for the Republic of Ireland, heading into their crucial World Cup qualifier against Hungary.

Heimir Hallgrimsson's side are third in Group F, a point behind their opponents on Sunday, and three behind leaders Portugal.

Ireland are fresh from a credible 2-0 victory over the latter on Thursday, thanks to Troy Parrott's brace at the Aviva Stadium.

The Boys in Green must now repeat those heroics at Puskas Arena, where only a win will keep their qualification hopes alive.

"This result [against Portugal] hasn't defined us yet," Ogbene told BBC Sport NI. "We have to go to Hungary with a level head, and we must win.

"It's all or nothing, really. We can't go there and try to get a draw as it won't do us any good, so we need to win this game.

"We know it's going to be difficult, and they will know we have to win, so they will be doing everything in their power to frustrate us. We just have to take this momentum and this feel-good factor into Sunday."

The foundations of Ireland's win over Portugal were laid by a superb defensive display, as they kept the likes of Cristiano Ronaldo at bay.

Ronaldo's frustration eventually got the better of him when he was shown a straight red for elbowing Dara O'Shea, an incident Ogbene believes was testament to the stubborn efforts of his team-mates.

"Frustration can kick in and happen to the best of us," he added. "Cristiano Ronaldo is one of the best players in the world, if not the best, and it happened to him, but that's credit to the boys and how they defended."