By Gabriel Tan in Manila
The Azkals were unable to commemorate their first-ever game in Southeast Asia's premier international tournament on home soil with a win on Saturday, as they had to hold out for a draw against a dangerous-looking Singapore side at the Rizal Memorial Stadium.
Nonetheless, Weiss believes the fact that the Lions failed to net a vital away goal, despite having a glut of chances to do so in the opening 45, leaves his side in a good position ahead of Wednesday's second leg in Singapore.
"We have every reason to be confident," he said. "I regard our chances as very good.
"0-0 is not a win but it is also a good result. If we score one goal there [in Singapore] they have to score two [to win].
"A victory or a draw with goals will put us in the final and that's what we're working towards. With this solid defence, it won't be easy for Singapore to score, even on home soil.
"It is now up to Singapore to be more active on home soil, and that might not be the worst scenario for us."
The German did however admit his side had given their opponents too much room to manoeuvre in on Saturday evening, which resulted in Singapore's first-half dominance.
"I think we saw two halves today [Saturday]," Weiss added.
"First, my team was scary [for me] as they were sitting too deep. We invited Singapore to build up and distribute the ball and it created a difficult situation for the backline.
"I wish the team had pushed forward earlier as it would have been easier for us."
Weiss also conceded midfielder Jason de Jong's display on Saturday was far from satisfactory, and while it was Marwin Angeles who replaced him at the break, the Azkals boss hinted it could be a different man who starts next Wednesday.
"I made a change at halftime because in midfield, Jason de Jong's misplaced passes were too much," he explained. "It paid off as Marwin had a good game and it got better after he came on.
"The midfield is crucial and if players don't pick the right passes, we spend the game on the defensive and are unable to threaten on the offensive.
"We're still not playing to our best potential but it was okay. A normal performance means we can only get better.
"We have Jerry Lucena available for the second leg, which will definitely help us in midfield."
Apart from the probable introduction of Lucena into the Philippines engine room, Weiss also revealed he would be tempted to make a couple of other changes to his starting XI.