Gamba Osaka received a rude welcome back to the Asian Champions League as the Japanese treble winners were dealt a 2-0 defeat at the hands of Guangzhou R&F in their start to the campaign on Tuesday.

The 2008 champions, back in the ACL for the first time in three years, fell behind early when Abderrazzaq Hamedallah struck on the break and conceded a late second, Wang Song’s free kick finding the net off the Gamba wall.

In South Korea, Kashiwa Reysol took a point off Jeonbuk Hyundai Motors in a Group E 0-0 draw after qualifying for the competition via the playoff last week.

Kenta Hasegawa’s men will try to make up for the Group F defeat on Saturday, when they face Urawa Reds in the Fuji Xerox Super Cup, the J. League curtain-raiser.

Gamba’s next ACL game is on March 3, when they play Seongnam FC away.

“I don’t think our performance was that bad, but the result is,” said Hasegawa, who missed Japan midfielder Yasuyuki Konno due to an injury. “We were watching out for their counterattacks. But we weren’t as tight as we should’ve been.”

“They’re extremely hard to break down. When they score, they slam the door shut and keep it locked. This was our first game so I can’t sit here and say that we were at our absolute best.”

“We’ll try to get back up next time.”

The visitors opened the scoring in the 10th minute through Hamedallah, who had 22 goals in 22 appearances in the Chinese Super League last season.

Hamedallah took advantage of some poor defending from Gamba, who had the striker swarmed in the box but still allowed him to fire away from a tight left angle.

Gamba nearly equalized in the 68th minute with a free header from Shu Kurata’s cross, but a reflex save by Liu Dianzuo kept the scoreline intact.

With 10 minutes left, Cosmin Contra’s side made it 2-0 against the run of play as Gamba poured it on, captain Yasuhito Endo needing to foul to stop Hamedallah on the run.

Wang curled a 20-meter free kick into the wall, but it deflected off Patric’s head, wrong-footing goalkeeper Masaaki Higashiguchi, who could only watch the ball roll past his line and doom the hosts in the process.

On Wednesday, Kashima Antlers launch their season at home to defending champions Western Sydney Wanderers, while Urawa Reds are away to Suwon Samsung.