Jakarta. Indonesian national football coach Alfred Riedl is focusing on mental aspects hampering his squad ahead of the second-leg semifinal of the Asean Football Federation Cup against Vietnam in Hanoi on Wednesday (07/12).

Riedl's team won by 2-1 in the first leg at Pakansari Stadium in Bogor, West Java, on Saturday with President Joko "Jokowi" Widodo among the spectators.

The coach hinted that the mental aspect is currently playing a significant role in the team's preparations for the second-leg match.

"There's a difference [in performance] from when the boys play in training and in a real match," Riedl said during a press conference in Hanoi on Tuesday, as reported by Detiksport.

"In a real match, players are pressured by spectators behind the goals. This situation is not replicated during training. For me, this is a mental issue," the Austrian said.

Riedl expects Vietnam to show more intensity during the second leg as it enjoys a home-ground advantage, while Indonesia will play modestly in the same way it did in the first leg.

"I will watch out for Le Cong Vinh especially," Riedl said.

Neither of the two sides' coaches want to think about a penalty shootout – a scenario that often occurs in football's knock-out phases.

"I don't think about a penalty shootout scenario. In our minds, we only want to win convincingly and advance to the final," Vietnam coach Nguyen Huu Thang said.

The team that wins on Wednesday will either face Thailand or Myanmar in the final.