The Republic of Ireland squad launch their latest bid for play-off glory on Saturday evening when they face Denmark in Copenhagen with a place at next summer’s World Cup finals at stake.
Here’s a look at Denmark and what stands between them and Russia over two legs.
Since losing back-to-back qualifiers in Poland and at home to Montenegro in October last year, Denmark’s from has been hugely impressive.
They went unbeaten in their remaining seven Group E games to finish second behind Poland, who they defeated 4-0 in Copenhagen in September, and were only denied a fifth successive qualifier victory against Romania last time out by Ciprian Deac’s 88th-minute equaliser.
Age Hareide is well known to O’Neill, who was the Norwegian’s captain during their time together as players at Norwich. A tax accountant by trade, the 64-year-old former Molde, Manchester City, Canaries and Norway defender has won league titles as a coach in Sweden, Denmark and his native country, who he took to the play-offs for the 2006 World Cup finals.
Hareide has employed a series of formations during the campaign to date, switching between a back three and a back four, but preferring the latter in recent games. However, his team more often than not revolves around midfield playmaker Christian Eriksen sitting in the hole behind a front two or three.
Tottenham schemer Eriksen is the star of the Danish side and as well as pulling the strings for others, he contributed eight of their 20 goals during the group stage, three of them from the penalty spot. However, keeper Kasper Schmeichel, central defender and skipper Simon Kjaer and holding midfielders William Kvist and Thomas Delaney are also mainstays of the team, while former Arsenal frontman Nicklas Bendtner started against Romania.