The Brazilian scored his first from penalty the spot nine minutes before half-time and put daylight between the sides two minutes after the restart.
Asamoah Gyan, the league's top scorer, gave Al Ain hope with a spot-kick of his own with 12 minutes remaining but Ahmed Khalil scored a third for the visitors in injury time.
And despite Ismail Ahmed responding again for the hosts, it was not enough to deny Al Ahli a fifth win in a row in the league.
Second-placed Al Shabab kept the pressure on the leaders with a hard-fought 1-0 win at home to Al Dhafra on Friday.
Despite having Mahmood Qassim sent off just before half-time when he received a straight red card, Al Shabab's 10 men fought on and won it early in the second thanks to an Edgar Silva strike - the club's fourth successive 1-0 win in the league.
Al Jazira are now five points behind Al Shabab in third after drawing 4-4 in a remarkable encounter with 10-man Al Wahda on Saturday.
Walter Zenga's side looked well on course for victory after racing into a 3-0 lead inside 43 minutes thanks to an Ahmed Al Ghilani brace either side of a penalty from Abdelaziz Barrada.
Ismaeil Matar and Eisa Ahmed struck after half-time to reduce the deficit but when former Manchester City striker Felipe Caicedo grabbed a fourth after 69 minutes and Al Wahda's Adel Basulaiman was sent off for a second booking two minutes later, the game looked over.
However, Sebastian Tagliabue grabbed his 16th of the season with 12 minutes remaining and Ahmed notched his second of the game in the final minute to seal a superb comeback.
Al Shaab are now six points from safety after losing 2-1 at fellow strugglers Ajman.
The home side were just four points and one place ahead of Al Shaab before the game but Mohamed Al Antaly gave them an early lead before Bakari Kone doubled their advantage after 32 minutes.
And despite Ahmed Jumaa's reply four minutes later, the home side held on to claim a fourth win of the season, which moves them up a place into 11th, while condemning Al Shaab to a fourth defeat in five league games.
Emirates dropped below Ajman after losing 2-1 at Bani Yas on Sunday. Salim Al Ali opened the scoring and although the visitors equalised courtesy of Gustavo Herrera's 27th minute penalty, Bani Yas won it with a second-half Nawaf Mubarak Musabh effort.
Dubai remain rooted to the bottom after their goalless draw at Al Wasl, while Al Sharjah and Al Nasr remain fourth and fifth respectively after their goalless draw.
