Rampant Al Sadd made it six wins from six in the Qatari League with a 4-1 away win at Al Rayyan.
After 54 minutes the scores were level - Nilmar having cancelled out Hisham Khalid's 12th minute opener - but Jung-soo Lee restored Al Sadd's lead inside two minutes. Raul (78) and Yusef Ahmed Ali (90) extended the margin.
Second-placed Al Wakra lost ground after Umm Salal grabbed a late 3-2 win.
Al Wakra's Younis Mahmood scored twice in the first 22 minutes, the second a penalty, but Mohiyaddin's 73rd minute strike, as well as a brace from Mahir Yousef (34, 89) turned the game on its head.
Bottom club Al Khrityat remain winless after a last-gasp defeat at Qatar SC.
Alain Dioko gave the basement boys a 67th minute advantage before Aghily Anwar's penalty and Mohamed Omar's effort won it for the hosts in the final three minutes.