Second-placed Lekhwiya lost ground in the Qatari League title hunt as they suffered a surprise 1-0 home defeat against struggling Al Khrityat on Monday.
Abdul Aziz Al Ansari netted the game's only goal after 26 minutes to earn his side just their fourth victory of the season, which lifted them a position to ninth in the 12-team league.
Lekhwiya remained five points adrift of leaders Al Sadd after 19 games.
Al Gharafa climbed to fifth spot thanks to a 2-1 triumph over fourth-placed Al Rayyan, early goals from Alex and Fahad Al-Shammari putting the hosts in the ascendancy before Ahmed Alaaeldin's late consolation.
Finally, Umm Salal moved up to seventh position after a 1-0 success away from home, Said Boutahar's 74th-minute strike sinking second-bottom Al Arabi.