High-flying Muang Thong United were shocked on their return from AFC Champions League (ACL) duty as Thai League (T1) strugglers Thai Honda beat them 1-0 on Sunday evening.
The league leaders suffered their first ACL defeat of the year when they lost 2-1 to Japanese champions Kashima Antlers on Wednesday. While there was no shame in a narrow reversal in Japan, losing to a side who had lost five in a row registered the biggest shock in T1 this year.
Elsewhere, Diogo Luis Santo was hero and villain as Buriram United closed the gap on Muang Thong to four points, while Sarawut Masuk made a welcome return for Bangkok Glass.
Here are five things we saw on T1 Matchday 14:
1. Jet-lagged Kirins given reality check
When Buriram lost their second game in a row last weekend, it looked as if the T1 title race this year may simply be a procession for Muang Thong United. The Kirins had opened up a seven-point gap at the top, and looked like overpowering any opponents that stood in their way.
Qualification for the knockout stages of the ACL added to the aura of the Thai champions, and a trip to face a Thai Honda side in free fall looked like a straightforward task.
In the 16th minute of Sunday's game, Sittichock Kannoo's long-range effort was beaten out by Kawin Thamsatchanan. Thanawit Kanma managed to get on the ball and hook it over Tristan Do before firing an angled shot through Kawin's legs. It looked as if the shot may be going wide, and Thawin Butsombut was on hand to turn the ball into an empty net.
With over three quarters of the game left, this looked a minor setback for the champions. But the hosts were by no means under pressure for the remainder of the game. They had several chances of their own before a late rally from the visitors almost turned the match around.
Inconsistent Thai Honda have now won four games this season, and their victims include last year's top three -- Muang Thong, Bangkok United and Bangkok Glass. If they can start beating the weaker teams, they may well be able to stay in T1.
2. Diogo makes most of Buriram reprieve
Buriram United looked on the way to their third defeat in a row when Sukhothai took a deserved lead through Kabfah Boonmatoon with 20 minutes remaining on Saturday. The Fire Bats had dominated the first half, and looked like getting their reward.
But six minutes later, the Thunder Castle pulled level through a highly controversial penalty decision. Diogo seemed to simply throw himself between two defenders and onto the ground, and the referee gave Buriram the chance to equalise.
Home fans were even more furious eight minutes later when the visitors were awarded a second penalty, though this time it looked the right decision after a pull on Jaja Coelho. Diogo struck again and grabbed his hat trick with a free kick five minutes into added time. The set piece followed a red card for Sakdarin Mingsamorn for a last-man foul on Jaja.
Diogo's intervention may have saved head coach Ranko Popovic's job and dragged his team back into title contention. But Sukhothai fans will be furious that a fine performance was rendered meaningless.
3. Vidmar hails return of AFF hero Sarawut
Bangkok Glass head coach Aurelio Vidmar was delighted to see winger Sarawut Masuk back on the pitch after the Thai international came on to turn the game against BEC Tero Sasana. 2016 AFF Suzuki Cup hero Sarawut had yet to feature this season before Vidmar introduced him as a second-half substitute with the sides locked at 1-1.
Chatree Chimalay had given the visitors a 41st-minute lead before Wichan Nantasri swiftly levelled the score. With Bangkok Glass dominant, but unable to find a cutting edge, Vidmar turned to Sarawut. The winger would deliver, with the assist for Jhasmani Campos' excellent winning goal.
"When Sarawut came on, he looked very sharp," said Vidmar. "He created a lot of confusion for the defenders. It was nice to have him back because he's a very important player.
"It has been a long time that he has been out after ankle surgery. It was an encouraging performance and he just needs to build his fitness."
The Glass Rabbits have had several injury problems this season, and Vidmar admitted that they had taken their toll.
"We've had two cruciate ligament injuries, one medial ligament injury, and ankle injuries and that's been a bit hard to take," Vidmar told ESPN FC.
"What I like about this group is that I don't see us as having 13 or 14 players, I think it's a deep squad when we're all fit. And the players who come in have always made a difference for us. These were three important points because Tero had been sitting just two points behind us."
4. Angels go goal crazy again
Bangkok United may not be challengers for the T1 title this year, but they may be the most fun to watch for the neutral fan. On Saturday, Mano Polking's side dismissed the challenge of Sisaket with a 5-1 victory, in which Mario Gjurovski followed up last week's hat trick with a brace.
This means that five of United's last six games have featured at least six goals. An incredible nine out of 14 games involving the Bangkok Angels this season have produced six goals or more. United have scored four goals or more on six occasions this year.
Bangkok United may not be demonstrating the ruthless consistency of 2016, but they are certainly showing that they can still be deadly on their day.
5. Marques puts his shirt on victory
Chonburi fans weren't best pleased with their top scorer Renan Marques at half-time on Friday. The Brazilian striker swapped shirts with an opponent as the Sharks trailed 1-0 to Marques' former side Chiang Rai United after his countryman Felipe Avezedo had scored a penalty.
But what appeared to be a weak show of deference might have been a cunning psychological ploy. Marques may simply have been lulling his dominant opponents into a false sense of security.
The second half saw a complete turnaround as Fode Diakite equalised before a double from Marques won the game for the hosts.
Marques' mind games have piled the pressure on Beetles' boss Alexandre Gama, with big-spending Chiang Rai having won just two of their last seven T1 games.