Ireland manager Giovanni Trapattoni has urged his players to keep the faith at Euro 2012 after their long unbeaten run came to an abrupt halt against Croatia in rainy Poznan on Sunday.

A mistake-riddled 3-1 defeat in their opening Group C match means they must avoid defeat on Thursday against world champions Spain who drew 1-1 with Italy.

"It's important we recover psychologically and believe again because we have to remember how many games we had played without conceding a goal," said the Italian. 

Whether or not the wily Trapattoni will risk tinkering too much against the world champions is doubtful although he did offer some encouragement for the fringe players.

"Spain is another game and then we have to think very, very much," the 73-year-old, who tasted only his third competitive defeat as Ireland boss and his first on the road, said.

"If I decide to change, it will not be because a player played badly or does not deserve to play. We have another game. Our opponent only drew and has only one point." 

Defender Stephen Ward said they would be huge underdogs against the Spanish but hoped the luck of the Irish would return after two of Croatia's goals owed much to large slices of fortune.

"Against Spain we have nothing to lose so we have to go out and give it everything and hopefully we can get a bit of luck on Thursday and then go into the Italy game with a chance of qualifying," he said.