By FOX Sports staff
Heading into the game at the Tuanku Abdul Rahman Stadium sitting third on the table with 10 points from their opening five games, B. Sathianathan's charges found themselves trailing after Firdaus Azizul opened the scoring in the 37th minute.
Although the visitors had their fair share of chances to equalise, it looked as though Negri were going to hold out for their first win of the campaign until a minute from time, when Norfazly Alias bombed forward and scored to earn ATM a share of the spoils.
The draw, coupled with other results, saw the Gladiators fall to fourth, ahead of Darul Takzim only on goal difference after Fandi Ahmad's side beat T-Team 1-0.
Dani Guiza netted the only goal of the game - his fourth in the league this season - to hand Harimau Selatan all three points at the Tan Sri Dato Hj Hassan Yunos Stadium.
LIONSXII leapfrogged Pahang into second place after beating Tok Gajah 3-0 at the Jalan Besar Stadium.
Although Dollah Salleh's side have been one of the standout teams of 2013 so far, they just had no answer to their Singaporean opponents, who took the lead in the 13th minute thanks to a close-range strike from debutant Faris Ramli.
Both sides then had goals correctly disallowed early on in the second half before the LIONSXII went on to seal the win with headed goals from Safuwan Baharudin and Fazrul Nawaz.
In the day's early kickoff, PKNS FC recorded an impressive 3-1 away win over ten-man FELDA United.
Having taken a 28th-minute lead through Helmi Remeli, PKNS looked on track for a routine win when opposition defender Nizam Abu Bakar was shown a red card two minutes after the half-hour mark, but a minute later, the hosts were level thanks to a Mohammed Ghaddar strike.
Unfortunately for FELDA, the numerical deficit eventually took its toll and the Red Ants reclaimed the lead a minute before the break through Patrick Ronaldinho Wleh, before Nazrin Syamsul wrapped things up by adding a third in the 55th minute.
On Friday, Selangor moved top of the table with an impressive 2-0 win over Kelantan, whose hopes of winning the title for a third straight year now look in serious doubt.
Liberia international Francis Forkey Doe opened the scoring for the Red Giants with a looping header in the 13th minute, before centre-back Ramez Dayoubg added a second three minutes before the half-hour mark when he powered home a good cross from Mahalli Jasuli.
Terengganu picked up their first win of the campaign after seeing off Perak 2-0 at the Sultan Ismail Nasiruddin Shah Stadium courtesy of goals from Ashaari Shamsuddin and Jean-Emmanuel Effa Owona.
Saturday's Malaysia Super League Results
FELDA United 1-3 PKNS FC
Negri Sembilan 1-1 ATM
Darul Takzim 1-0 T-Team
Friday's Malaysia Super League Results