By Gabriel Tan in Bangkok
The War Elephants head into Saturday's game at the Suphachalasai Stadium trailing by two goals on aggregate after falling to a 3-1 defeat to Singapore in Wednesday's first leg at the Jalan Besar Stadium.
Although Thailand have spent much of the tournament dominating their opponents en route to the final, many believes they struggled to cope with the Lions' aggressive ways as they heavily pressured from the opening whistle.
Nonetheless, Teerasil believes his side have learnt from Wednesday's game and reveals they are ready to match their opponents in ferocity when they meet again.
"Not to worry," he told ESPNSTAR.com, when asked if Singapore's aggression was something that might pose a problem once more on Saturday.
"We're ready to do battle and do whatever it takes to get the victory that we need.
"Everybody's ready for Saturday. Our goal remains the same and we're ready to make history."
The Muangthong United striker was referring to the fact that whoever emerges triumphant would become the first side to win Southeast Asia's premier international competition on four occasions.
Although Singapore's last title came in 2007, the War Elephants have not lifted the Suzuki Cup in a decade.
They twice finished runners-up in 2007 and 2008 and also fell to embarrassing group-stage exits in 2004 and two years ago, and it's perhaps slightly understandable why fans no longer flock to support Thailand like they used to do in the early days of the competition, when they won three of the first four editions.
As such, Teerasil admits winning the Suzuki Cup could mean so much more than just a record fourth title.
"I would be absolutely proud to be part of the team if we can do it on Saturday," the 24-year-old added.
"I think it will be a turning point in Thai football. Hopefully it will get the fans back supporting the national team again."
While a overturning a two-goal deficit is by no means an easy feat considering the Lions have only conceded once in their last three games, Teerasil believes the away goal they scored in Singapore could prove to be priceless if they are capable of opening the scoring on Saturday.
"Obviously it should be an advantage to have an away goal but it's not going to be an easy game for us by any means," he conceded.
"We still have to keep to our game and do our best. Whoever scores first is likely to take the advantage in the tie.
"I hope tomorrow [Saturday] that team is Thailand."
A Thailand victory would cap off a remarkable year for Teerasil, who was part of the Muangthong side that coasted to the Thai Premier League title after finishing the season unbeaten.