It was an intriguing opening round in the Malaysia Cup with Premier League runners-up Sime Darby, PKNS and Negri Sembilan causing the biggest upsets yesterday.
Second-tier teams Kedah and Johor were also able to hold fancied sides to draws.
Sime Darby condemned Armed Forces to their sixth straight defeat by edging last season's finalists 4-3 in a Group A match at Selayang Stadium.
Sime Darby stunned Forces with a third minute goal through Premier League top scorer Karlo Primorac of Slovakia while Togo's Togaba Kontiwa Komlan (24th), Hadzirun Hamid (32nd) and Fazrul Hazli (46th) each added a goal.
Forces reduced the deficit through an own goal by Sime Darby's Firdaus Faudzi (16th), Irwan Fadzly Idrus (58th) and Venice Elphi (75th).
Sime Darby coach Ismail Zakaria said: "It is a good start to our campaign. We knew Forces would come back strongly but we held our nerves for the precious win."
In Pasir Gudang, group favourites Selangor were held 0-0 by Johor.
In Group B, PKNS stunned 10-man Darul Takzim 2-0 at Shah Alam Stadium. Patrick Wleh netted a brace in the 16th and 57th minutes to take his tally to 16 goals this season.
Darul Tazim goalkeeper Al-Hafiz Hamzah Mohd was red carded in the 65th minute for handling the ball outside the penalty box in the match.
The defeat came just a day after the club announced the resignation of team manager Fandi Ahmad.
Despite having the best players in the competition, the unmotivated Johor side failed to make their presence felt and coach Azmi Mohamed will need to mend the team before their next match.
T-Team earned a morale-boosting 1-0 win over Felda United at Temerloh Stadium. Former Aston Villa midfielder George Boateng struck the ball from outside the penalty box past Felda goalkeeper Helmi Eliza Alias in the 47th minute on a water-logged pitch.
T-Team coach Che Ku Marzuki Mohd Noor said: "Despite playing under tough weather, we managed to hold our ground and claim a win."
In Group C, Negri Sembilan earned only their fourth win of the season by upsetting Terengganu 2-0 at Sultan Nasiruddin Shah Stadium. Fabio Leandro Barbosa and S.Sivanesan scored in the 40th and 54th minutes for three points.
In another match, Damion Stewart's header five minutes from time earned Pahang a 1-1 draw with defending champions Kelantan at Darulmakmur Stadium.
Kelantan captain Badhri Radzi put the visitors ahead in the ninth minute before Stewart's equaliser in the 85th minute.
Both teams had a player sent off. Kelantan's Ahmad Fakri Saarani received his marching orders for a second yellow card in the 63rd minute followed by Pahang's R.Surendran's dismissal 10 minutes from time.
Alen Guc's penalty strike in stoppage time earned Premier League outfit Kedah a 2-2 draw with Super League champions LionsXII in a Group D at Jalan Besar Stadium.
Lions gave away a penalty when Shakir Hamzah fouled substitute striker Syafiq Ahmad in the third minute of stoppage time. Guc cooly put the ball past Lions goalkeeper Izwan Mahbud.
Lions dominated the opening minutes and netted their first goal through captain Shahril Ishak, who headed home from close range off a Fazrul Nawas' cross from the left in the 11th minute.
Undeterred, Kedah fought back gallantly and levelled proceedings in the 23rd minute. Khyril Muhymeen broke free on the right and his low cross found Guc, who scored on a rebound after his initial shot was blocked by keeper Izwan.
After the break, Kedah gave Lions some anxious moments but the homesters defended stoutly before taking the lead through Shafiq Ghani's spectacular free kick in the 66th minute.
Lions, however, were disorientated after Shahril Ishak suffered an injury to his knee and was replaced by Muhd Izzidin Shafiq Yacob in the 75th minute.
But Kedah stamped their dominance and scored the equaliser through Guc in the dying minutes.
In another match, Perak handed Sarawak their only second defeat of the season when they edged the Premier League champions 2-1 in a match which was stopped twice when fans threw firecrackers onto the pitch. Paulo Rangel scored a brace for Perak in the 65th and 81st minutes after Joseph Kalang Tie had put the visitors ahead in the 32nd minute.