Buriram United cannot afford any more slip-ups in the AFC Champions League after losing 2-0 at China's Jiangsu Sainty last night.
Buriram’s Chilean striker Ramses Bustos, white, shoots despite the pursuit of Jiangsu Sainty’s Sun Ke in Nanjing yesterday.
Jiangsu bounced up from bottom to second in Group E while the Thai FA Cup champions slipped to last.
In the other match in the same pool, FC Seoul survived a late fightback to beat Japanese visitors Vegalta Sendai 2-1 and extend their lead at the top of the group.
FC Seoul, who have seven points, appear likely to finish in the top two but the race for the other berth in the last 16 is still wide open, with Jiangsu on four points and Sendai and Buriram level on two points.
At the Olympic Sports Centre in Nanjing, Jiangsu dominated for long periods in the first half but had to wait until the 41st minute for their first goal.
Lu Bofei opened the scoring with a fierce long-range drive, followed moments later by Sun Ke's headed goal to give the hosts a 2-0 lead at half-time.
The Thunder Castle regrouped in the second half but could not break through Jiangsu's defence.
Buriram will host Jiangsu in the return leg on April 10.
In Seoul, FC Seoul were cruising after first-half goals from Sergio Escudero and Kim Jin-Kyu but they were forced to endure an anxious finish after Sendai's Brazilian forward Wilson reduced the deficit with an 87th-minute penalty.
In today's Group F match, SCG Muang Thong United need a result at China's Guangzhou Evergrande to avoid early elimination.
The Thai Premier League champions are bottom of Group F with one point from two games following a 2-2 home draw with South Korea's Jeonbuk Hyundai Motors and a 4-1 loss at Japan's Urawa Red Diamonds.
The Chinese are under Italy's 2006 World Cup-winning coach Marcello Lippi and Muang Thong coach Slavisa Jokanovic is determined to show him some impressive football.
''We want a top-class coach like Marcello Lippi to know more about Thai football and Muang Thong United. We hope to get at least one point,'' he said.
RESULTS
Group E
FC Seoul (KOR) 2 (Sergio Escudero 6, Kim Jin-Kyu 22) Vegalta Sendai (JPN) 1 (Wilson 87 pen)
Jiangsu Sainty (CHN) 2 (Le Bofei 41, Sun Ke 42) Buriram United (THA) 0
STANDINGS
P W D L F A Pts
FC Seoul 3 2 1 0 7 2 7
Jiangsu Sainty 3 1 1 1 3 5 4
Vegalta Sendai 3 0 2 1 2 3 2
Buriram United 3 0 2 2 1 3 2
TODAY'S FIXTURES
Group F
At Saitama: Urawa Red Diamonds (JPN) v Jeonbuk Hyundai Motors (KOR) 5.30pm
At Guangzhou: Guangzhou Evergrande (CHN) v Muang Thong United (THA) 7pm