While Europe’s FIFA World Cup™ qualifiers are seen as a marathon rather than a sprint, the play-offs always represent that frantic final dash for the finish line.

With no margin for error, and just four places to divide between eight formidable sides, these two-legged ties always deliver on drama, tension and passion.

Who could forget, for example, Slovenia stunning Russia in the 2010 qualifiers, or Portugal’s Cristiano Ronaldo-inspired victory over Sweden four years ago? It’s worth remembering, too, that Germany required a play-off to qualify for the 2002 World Cup before going on to reach the Final.

With this decisive stage looming once again, FIFA.com looks at the ties and the teams involved.

Northern Ireland-Switzerland No European team has ever failed to reach the World Cup after earning 27 points during the group phase, and Switzerland will be confident of avoiding becoming the first. They have qualified for each of the last three editions and were only edged off top spot by Portugal at the end of an erstwhile flawless group campaign. But Northern Ireland, having proved that their UEFA EURO 2016 heroics were no fluke, will be out to claim another high-profile scalp. They are aiming to reach their fourth World Cup – and first since 1986.

Croatia-Greece This tie brings together two veritable play-off specialists. Greece are aiming to become the first European team to reach three successive World Cups via the play-offs, having seen off Romania and Ukraine en route to the 2010 and 2014 editions. But they will start as underdogs against a star-studded Croatia side boasting an unmatched and unblemished record of play-off victories. They have triumphed in all four of their previous qualifying play-offs for major tournaments and, with the likes of Luka Modric, Ivan Rakitic, Mario Mandzukic and Ivan Perisic to call upon, will be confident of making it five out of five.

Sweden-Italy Only two teams, Brazil (21) and Germany (19), have qualified for more World Cups than Italy, and Gli Azzurri can draw level with the Germans should they edge out Sweden. They have come through a play-off once before – beating Russia on their way to France 1998 – but will have their work cut out against a revitalised Swedish side. Indeed, Janne Andersson’s side are the highest scorers of the eight play-off contenders, having found the net 26 times during the group phase.

Denmark-Republic of Ireland No European team has participated in more qualifying play-offs for major tournaments than Republic of Ireland. This will be their eighth overall, and they have mixed memories of three memorable triumphs – such as beating Iran to qualify for the 2002 World Cup – and four devastating losses, among them an infamous defeat to France in 2009. Denmark, though, will start as favourites - “rightly so” according to Martin O’Neill. They are a team the Irish have not beaten in a competitive match since 1979, and Age Hareide’s in-form side go into this match having not tasted defeat in over a year.

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The player Christian Eriksen has scored in each of his last six appearances for Denmark and is only the third player in the team’s history to rack up such a run. Martin O’Neill has lauded the Tottenham Hotspur midfielder as “one of the best in the world”, while Age Hareide suggested he could be “the difference” in a tie most pundits expect to be tight.