Tuesday marks the start of the decisive phase of the FIFA U-20 World Cup 2013 with the first four of the eight round-of-16 ties. For the nations involved, there are only two options in Istanbul and Gaziantep: go through, or go home.

Tuesday’s matches feature teams from five continents, but of the eight in action on the day, only favourites Spain took maximum points from their group matches. Elsewhere, momentum is building behind hosts Turkey as the fans sense a potential triumph. FIFA.com previews the action.

The Schedule
Tuesday 2 July (all times local)
Round of 16, Matchday 1
Spain-Mexico, Istanbul, 18:00
Greece-Uzbekistan, Gaziantep, 18:00
Nigeria-Uruguay, Istanbul, 21:00
France-Turkey, Gaziantep, 21:00

Match of the Day
Football fans up and down the country will be focusing their passions on Gaziantep, where the young Turks go in search of a place in the last eight against France. Coach Feyyaz Ucar’s side won two of their three group matches and will be confident of progressing, especially with talented Hamburg-bound playmaker Hakan Calhanoglu running into peak form, a fact underlined by his superb strike against Australia last time out. “We're growing as a team," he told FIFA.com.

The Turks will have to do without Ibrahim Yilmaz, who picked up his second yellow card of group stage during the game with the Socceroos, but Les Bleuets are also without towering Olympique Lyon defender Samuel Umtiti through suspension. On the plus side for the French, Juventus schemer Paul Pogba returns after serving out a ban. Pierre Mankowski's men are slight favourites going into the match, for although a group stage record of a win, a draw and a defeat is modest at best, it does suggest the French have yet to play to their full potential and could easily move up through the gears. Another fascinating dimension to the contest is the clash between the agile, individually skilled hosts and Mankowski's physically powerful team.

Other Highlights
Spain versus Mexico promises high tempo football and slick short passing from both teams. Quite a few pundits thought the encounter would take place at a later stage of the tournament, but while the 2012 U-19 European champions cruised through the group stage with a perfect record, the 2011 U-17 world champions made surprisingly heavy weather of the preliminary phase and only just squeezed through as one of the best third-placed teams. La Rojita will again be looking to four-goal Jese and pacy winger Gerard Deulofeu for inspiration, with El Tri forced to compensate for the loss of influential midfielder Jesus Escoboza to suspension.

Newcomers Greece potentially face an uphill struggle against one of the surprise packages of the tournament so far. Uzbekistan shipped four goals without reply in a heavy defeat to Uruguay in their last group match, but they had previously laid down impressive credentials as a tough team to beat. Defender Maksimilian Fomin returns from suspension, and the Greeks will also be at full strength as they aim for a last eight berth on their tournament debut.

The Nigeria-Uruguay encounter promises an absorbing clash of styles, although in terms of their form, the teams are on an identical track: both lost their opening match but then won the next two and finished second in their groups. And many people rate the teams as a good outside bet for the trophy. “We'll get even better," Uruguay midfielder Geno Acevedo told FIFA.com, issuing a warning to the muscular west Africans.

Player to watch
Abbosbek Makhstaliev (Uzbekistan)
The Pakhtakor Tashkent starlet stands a mere 1.69m tall, but he is an exceptionally gifted footballer and highly adept at injecting pace into his team's attacks. He has had a hand in three of the Uzbeks’ goals at the tournament so far, scoring one and laying on another two. The 19-year-old, who finished with three goals and one assist at the FIFA U-17 World Cup 2011 in Mexico and is rapidly becoming the kind of player who can single-handedly decide a match, is determined to hit new highs against the Greeks.

The Number
10 - Spain have reached the knockout stages of this tournament series for the tenth time in a row. The last time they were forced to pack their bags for home after the group stage was as long ago as the 1989 finals in Saudi Arabia.

The Words

Suso, Spain midfielder