They may have needed a last gasp goal to defeat China PR in the quarter-finals but Saudi Arabia will head into the semi-finals confident of achieving victory against Korea Republic.

Marcos Soares' side have matured as the tournament has progressed, showing resilience and focus and the mood in the camp will surely be that a fourth title beckons.

By far the most successful team in the AFC U20 Asian Cup, Korea Republic are determined to emerge champions for the 13th time.

It has been a long wait as the last of their titles was won in 2012 and head coach Lee Chang-won will urge his players to remain focused after having already booked their ticket to the FIFA U20 World Cup Chile 2025.

Three of the four semi-finalists are former winners, with Australia the odd ones out.

The closest the Young Socceroos have gotten to lifting the trophy was when they finished runners-up in 2010. Confidence, however, is high within the squad that they can go all the way after a perfect campaign so far.

Japan are in the semi-finals but Yuzo Funakoshi's side had to work hard in Shenzhen. They opened with a 3-0 defeat of Thailand in Group D but that was followed by draws with Syria and Korea Republic.

The East Asian side then needed penalties to beat Islamic Republic of Iran in the quarter-finals and unless they find their form, Australia will be extremely tough opponents on Wednesday.

The Video Assistant Referee (VAR) will be in play in the semi-finals and final, adding another touch of intrigue to a tournament that has more than lived up to expectations. It will be the first time that VAR will be used in the AFC U20 Asian Cup.