The Junior Boks would have been happy with the victory, but there is still a lot of room for improvement, especially at lineout time.
However, they showed great character in the second half to overturn a 7-21 half-time deficit into a two-point victory in the match played in sunny conditions with a light wind, a welcome respite after the rain in the first two rounds.
After a great start, with Jurenzo Julius (outside centre) scoring a try in the opening exchanges from a turnover at the kick-off, the South Africans allowed Argentina back into the game through a combination of unforced errors, bad decision making and losing possession on the ground.
They showed some good intent on attack early on, and when asked were solid on defence, but the Junior Boks lost their first four lineouts, a few of them deep in Argentine territory, which is inexcusable at international level.
Their scrums were solid for most of the match and they applied a lot of pressure in this phase in the second half, there were more lineout woes for the Junior Boks after the break, resulting in the team opting for quick-tap penalties in the Argentinean 22 - a tactic that had the desired effect in the end.
After the Junior Boks' strong start, Argentina slowly built confidence on the back of forward ascendancy, and scored their first try after 27 minutes when Franco Rossetto (left wing) went over after they found space on a small blind side from a ruck inside their own half, and Facundo Rodriguez's (flyhalf) conversion made it 7-7.
A few minutes later, Ezekiel Ngobeni (scrumhalf) was yellow carded for a dangerous tackle and when he came back early in the second half, it was 21-7 to Argentina as Rossetto added two more tries to his tally, with Los Pumitas making the most of their numerical advantage to allow their speedster a first-half hat-trick.
Whatever Junior Bok coach Bafana Nhleko said during the break, clearly made an impact as the SA U20s came out firing. After another attacking lineout going awry, the tireless Tiaan Jacobs (No 8) crashed over from a quick tap penalty with Van Niekerk's conversion making it 21-14 in the 46th minute.
Ten minutes later, Casper Badenhorst (replacement prop) also barged over from a tap penalty in the Argentinean 22, but the conversion went wide and suddenly it was a two-point game.
When Argentina were shown a yellow card with just under 15 minutes to go, the Junior Boks took their chance with a penalty goal by Van Niekerk, followed by a third try from a tap penalty by SA U20 captain Zachary Porthen (prop) to put them in a 27-21 lead.
Rossetto gave Los Pumitas some hope with his fourth try five minutes before the end, and Santino Di Lucca's (replacement back) sideline conversion gave Argentina a one-point lead, but the Junior Boks held their composure, worked themselves into a favourable field position and Van Niekerk did the rest after the hooter had sounded.
Scorers:
Junior Springboks 30 (7) - Tries: Jurenzo Julius, Tiaan Jacobs, Casper Badenhorst, Zachary Porthen. Conversions: Philip-Albert van Niekerk (2). Penalty goals: Van Niekerk (2).
Argentina 28 (21) - Tries: Franco Rossetto (4). Conversions: Facundo Rodriguez (3), Santino Di Lucca.
