Second-place Al-Nasr came from behind to win 2-1 at Ajman and move to within three points of the leaders, while Ricardo Oliveira scored four as Al-Jazira thrashed Sharjah 5-0 to sit a point further back.
Boris Kabi put Ajman in front, but Marco Bresciano levelled in the 28th minute and former Italy striker Luca Toni got the winner 11 minutes from time.
Al-Jazira found things rather easier against second-bottom Sharjah, with Oliveira opening the scoring with a 34th-minute penalty and doubling the lead before the break.
Abdulla Mousa made it three early in the second half before Oliveira struck twice more to complete the rout.
Elsewhere, Al-Wasl and Bani Yas drew 0-0.