True Bangkok United, hoping to lift their maiden Thai League 1 trophy this year, face first real test of their title credentials on Sunday when they host defending champions Buriram United.
The capital side have already felled another giants, SCG Muang Thong United, this term, securing a 1-0 home win against the Kirins thanks to Nelson Bonilla's strike.
Bangkok United signed several new players during the close season, including Thailand defender Tristan Do and his former national team colleague Peerapat Notechaiya, both from Muang Thong.
Buriram are high on confidence after shocking South Korean champions Jeonbuk Hyundai Motors 1-0 in an AFC Champions League Group G game on Wednesday.
However, Thunder Castle assistant manager Sirichai Kimoto is worried, saying the win over Jeonbuk had come at a price.
"Some of our key players were injured in the Champions League game, including Supachai Chaided and Andres Tunez," Sirichai said, adding: "But we are hoping they will be available for Sunday's big match.
"We are not expecting an easy game at Bangkok United because they are a strong team and are unbeaten in the league so far. However, we are heading to Bangkok with high hopes of claiming three points."
Bangkok United assistant coach Watsapol Kaewpaluek said: "It will be another tough game for us. Buriram are a strong team even without [former star striker] Diogo Luis Santo. However, we are hoping to pick up a point from this game."
Buriram struggled in their first two games of the season in the absence of Diogo, who was sent to Malaysia's Johor Darul Ta'zim in a deal that reportedly earned the Thunder Castle 100 million baht.
Meanwhile, Muang Thong coach Phairoj Bovornwattanadilok will be under the microscope tonight when the Kirins face last year's FA Cup and League Cup winners Chiang Rai United away.
Phairoj said his team were slowly getting back into the groove after their close win over newcomers Chiangmai last weekend.
"Chiang Rai have some good players but I think we can handle that and we hope to pick another win this weekend," added the Kirins coach.
League leaders Port will be fancying another week at the top as they take on recently promoted PTT Rayong at their home ground on Sunday.