Martin O'Neill has warned the Republic of Ireland they may have to score twice to beat Denmark to a place at the World Cup finals in Russia. O'Neill's men emerged from their play-off first leg trip to Copenhagen with a hard-fought 0-0 draw, but the 65-year-old manager was quick to admit that keeping Christian Eriksen and company quiet all over again in Dublin on Tuesday night may prove difficult. He said: "With the players that they possess, I believe that they are capable of scoring a goal, so it means we might have to score two to win the match. "That's the way I am looking at it, and we will have to show a bit more creativity during the course of the game at the Aviva. But I think we are capable of doing that. "Urged on by a big crowd as well ... We have a lot to play for, anyway." Ireland were indebted to goalkeeper Darren Randolph for their clean sheet at the Parken Stadium as he pulled off a string of fine saves to keep them level, although he was relieved to see Pione Sisto steer wide of an open goal after he had repelled Eriksen's first-half effort. O'Neill, who saw the Middlesbrough keeper tip a last-gasp header from substitute Yussuf Poulsen over the bar, said: "Darren Randolph is a very fine goalkeeper and I thought he made a very good save, an excellent save, and the one he tipped over the bar. "That's the way he's been playing for us during the course of this campaign. "The players put a big effort into the game. It would have been great if we could have scored a goal, but I think the game is evenly poised for the second leg. "[Denmark manager] Age [Hareide] said last night in the press conference that he thinks they are capable of scoring at the Aviva - I wouldn't doubt that. "We just have to win the game. We have to score goals to win the match. We would obviously want to be better with the ball in Dublin when we are playing in front of our home fans - and in all honesty, we will need to be if we have to score a goal." <strong>________________________</strong> <strong>Read more:</strong> <strong>________________________</strong> Hareide was disappointed after seeing his side threaten to take a meaningful advantage to Dublin, but hopeful that there is more to come. He said: "We created enough chances to win the game, at least three big chances. But we have to get the ball in between the posts, that's always important. We knew Ireland would be hard to break down and when you don't take the chances, they survive. "But 0-0 at home is not a bad result. A goal away will be very vital for us. They don't score two many times. We will go to Dublin and try to get that goal." Hareide was less than impressed at the suggestion that it had been a poor game and is confident a similar performance at the Aviva will see Denmark through. He said: "You can say what you want, but I wouldn't say it was a poor game. We created chances. We had the ball 65 per cent. We played well enough to win. "If we play like this in Dublin, we win. You can say what you want, that's your choice. I have my opinion, OK?"