Al Wasl recorded their first Asian Champions League win in more than a decade when Fabio de Lima's 62nd minute penalty helped them beat Saudi Arabia's Al Nassr 1-0 in Dubai on Tuesday.
The hosts were awarded the spot kick when striker Yousef Ahmed was brought down by Abdullah Madu inside the box, and Brazilian De Lima scored the only goal of the Group A match.
Al Wasl had nothing to show for their campaign in last year's tournament as they crashed out of the group stage in their first appearance in the competition since 2008.
However, they had the better of the exchanges the Zabeel Stadium and came close to scoring on a few occasions, De Lima himself firing high over the post early in the first half.
An attempt by Salem Al Azizi from inside the box was saved by Al Nassr's Australia goalkeeper Brad Jones, before De Lima again missed the target late in the second half.
Elsewhere in the same group, Iraq's Al Zawraa grabbed a valuable away point with a goalless draw against Iran's Zobahan.
Al Zawraa's appearance marked the first time an Iraqi club were taking part in the tournament since 2008 due to on and off-field issues and they acquitted themselves well against the vastly experienced Iranians.
The visitors missed a great chance as Jabbar Kareem's header off a Hussein Al Jwayed cross went just wide of the mark in the sixth minute.
Their defence also held firm, thwarting a couple of efforts from Zobahan as the match petered out late-on.
In Group B, Lokomotiv of Uzbekistan beat the UAE's Al Wahda 2-0 in Tashkent.
Temorkhuja Abdukholikov put Lokomotiv ahead just five minutes into the match with a header from a rebound, after his earlier header had deflected off the crossbar
Several Al Wahda efforts at goal were wasted but the hosts put the result beyond doubt in added time, captain Islom Tukhtakhujaev's fine free kick finding the top corner.
Meanwhile Saudi Arabia's Al Ittihad, sounded an early warning by thrashing Qatar's Al Rayyan 5-1 in Tuesday's second Group B match.
Gonzalo Viera had put Al Rayyan ahead in the 23rd minute but Fahad Al Muwallad equalised in the 45th minute and Abdulaziz Al Aryani netted in first-half stoppage time to put the hosts ahead in Jeddah.
Ziyad Al Sahafi and Abdulrahman Al Ghamdi added two more goals in the second half before Saudi Arabia international Al Muwallad struck his second goal in the 78th minute to complete the rout for the two-time former winners.
