The East Asian team suffered a painful 1-0 defeat in their opening fixture against Tajikistan, conceding to a spectacular Sharafjon Solehov strike after 77 minutes of tense, competitive football.

A similar result against group leaders Saudi Arabia could see Cheng's side eliminated on Tuesday, but the 51-year-old insists his team's campaign is far from over.

"Of course (we can still qualify). This is not the end for us," he said.

"This is football. Sometimes you win and sometimes you lose, but we still have a chance and we are looking forward to the next game."

In what proved to be a close fought encounter at Bekasi’s Patriot Chandrabhaga Stadium, Solehov’s stunning strike from fully 25 yards proved decisive as the Central Asians laid down an impressive early marker in Group D.

The victory saw Tajikistan go second in the group behind Saudi Arabia, and leave the 18-year-old happy that his side could execute head coach Mubin Ergashev’s pre-match plans.

Despite missing a first half penalty, the Al Shabab ace shone brightly against Saudi Arabia’s Southeast Asian opponents, scoring a well-taken opener and being an influential figure throughout the victory which saw the Young Green Falcons fly to the top of the Group D standings.

With the dust settling on his Player of the Match display, Al Ammar was however quick to praise his side’s united approach while promising that he is determined to improve even further in order to help Saudi Arabia’s cause both now and in the future.

The Croatian head coach was pleased with Harimau Muda's effort in their opening Group D clash, as the Southeast Asians ensured it wasn't only the humid conditions that made the two-time champions sweat.

"We are here as underdogs, playing against Saudi Arabia who are one of Asia's power teams and nobody expects too much, but we gave them a tough time," the former Johor Darul Ta'zim and Kelantan boss explained.

"I told the boys I am proud that they fought for all 90 minutes. I think that they were playing near maximum.

"Overall, I am not disappointed, I am proud. Of course, there are mistakes. There are always mistakes and if there weren't you'd win every game, but we are not at that level yet."

Sharafjon Solehov's precise 77th minute strike gave the Central Asians a 1-0 win at Patriot Chandrabhaga Stadium, putting them in a strong position to each the quarter-finals for the second consecutive edition of the competition.

Speaking after the match, a delighted Ergashev said the result was a fair reward for his young side's performance.

"China is a good team with good players, but we had more chances," he declared "We could have scored earlier also."

"In football the best team on the day is the winner, and I think Tajikistan was the best team in this game."

The 18-year-old rattled in a superb 25-yard effort to put the Central Asians in a strong position to qualify for the quarter finals, joining Saudi Arabia as Group D leaders.

Solehov's late winner broke a 77-minute impasse after the two sides, the last to make their first appearances on the Indonesia 2018 stage, had played out a tense contest with little between them.

Turki Al Ammar and Salem Al Saleem found the back of the net for the Saudis, who endured a tense finish after dominating most of the match, with Malaysia failing to register a shot on target until their 88th minute goal from Hadi Fayyadh.

The win puts the West Asian side in pole position in Group D as they look to reach a ninth FIFA U-20 World Cup by finishing as one of the top four teams in the competition.