The Brazilian has impressed since coming back into the fold for the Arabian Gulf League side.
Zoran Mamic delighted with contribution of Douglas in Al Ain's Asian Champions League stalemate with Al Hilal
Al Ain manager Zoran Mamic has praised Douglas’ character after the much-maligned forward marked his return to the first team with a fine display in the Asian Champions League.
The Brazilian, 29, has been brought back into the fray following last year’s final, when he missed a penalty in the second leg against Jeonbuk Hyundai Motors.
The South Koreans held on to take the title 3-2 on aggregate, with Douglas then omitted from the Al Ain squad for the second half of the 2016/17 domestic season.
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However, the striker has impressed Mamic in pre-season and was rewarded with his first competitive appearance of the year in Monday’s all-important clash against Hilal in the first leg of the quarter-final.
Despite the match finishing goalless - Al Ain played the final 25 minutes with 10 men following Mohanad Salem's red card - Douglas was a standout.
In the first half, he had a goal disallowed for offside, while he also forced a great save from Hilal goalkeeper Abdullah Al Mayouf in the closing minutes.
“Today, he was one of the best,” Mamic said. “He played very well, he gave everything for the team, he fought for the team. He fought for every ball and I’m very happy with his performance.
“Douglas is a great character - you have to be very, very strong to survive all this. But this is football, this is life.
"Bigger players than Douglas have missed penalties, but he feels support from the coaching staff, from the players and now today I saw the fans also happy with him. He will be great for us. He’s a really, really good character.”
Douglas played behind Marcus Berg in attack, with the Swedish international lasting 70 minutes on his debut.
A summer signing from Greek side Panathinaikos, he had started well, but visibly tired in the 39 degree heat.
“Marcus today didn’t play so very well because the team didn’t play at its top level,” Mamic said.
“So it was very hard for him: first official game at this top level, in these weather conditions.
“But Marcus is a great player and he will make the fans and me as a coach and the team very, very happy very, very soon. He needs games to adapt to this weather.
"It’s not easy, but he’s a great professional and I don’t worry that he will come up. In pre-season [in Austria] he was one of our best players - but in other weather conditions - and he needs time.”
Asked his thoughts on which team is better placed going into the second leg in Riyadh on September 11, Mamic said: “It’s difficult to say who is closer.
"We are satisfied with this result. We didn’t concede a goal, which is very important. And after three weeks I’m sure my team will be much more ready.”