Roberto Mancini played down Saudi Arabia's chances of winning the Asian Cup after they reached the knockout rounds with a laboured 2-0 victory over nine-man Kyrgyzstan on Sunday.

Kyrgyzstan had Ayzar Akmatov sent off in the ninth minute and Kimi Merk joined him seven minutes into the second half in Doha.

Mohamed Kanno opened the scoring for the Saudis in the 35th minute.

But the three-time champions -- ranked 56 in the world to Kyrgyzstan's 98 -- managed only one more late goal from Faisal Al-Ghamdi in a toothless attacking performance.

Mancini, who won the European Championship with his native Italy in 2021, said his team were lagging behind the favourites to win the title.

"The rankings say Japan, Korea, Iran, Australia -- and we are too far," he said.

"But you know in this tournament, when you play one game, everything can happen in one game.

"Now we are in the next stage but we have to think about the third game because we want to win."

The result gave the Saudis, who came back to claim a last-gasp 2-1 victory over Oman in their opening game, six points from two matches.

They lead Group F two points ahead of Thailand, who drew 0-0 with Oman earlier in the day.

Saudi Arabia joined hosts and holders Qatar, Australia, Iran and Iraq in booking their places in the last 16.

"I think we were missing many chances to score but if we score two goals every game, I'm happy," said Mancini.

"I hope that we can improve more for the next stage."

Akmatov was initially only yellow-carded for driving his studs into Sami Al-Naji's shin, but the referee flashed the red after a VAR check.

The Saudis could not immediately turn the numerical advantage into goals, with Feras Al-Brikan missing two golden chances to give them the lead.

The frustration looked set to continue when Abdulelah Al-Malki hit the post, but Saud Abdulhamid collected the rebound and crossed the ball back into the box for Kanno to volley home.

Already facing an uphill struggle, Kyrgyzstan were reduced to nine men in the 52nd minute after another VAR red-card check.

Merk's hefty challenge on Hassan Tambakti was judged to be a sending-off offence.

"I think they were very dangerous fouls," said Mancini.

"I think the two red cards were correct."

The Saudis again failed to capitalise, with Kanno shooting harmlessly over the bar in the 68th minute before Saleh Al-Shehri glanced a header wide 10 minutes later.

Substitute Ghamdi finally added a second goal in the 84th minute, letting fly with a shot from the edge of the box that Kyrgyzstan goalkeeper Erzhan Tokotaev fumbled into the goal.

Kyrgyzstan are still alive in the tournament heading into their final game against Oman on Thursday, the same day the Saudis play Thailand.

"We played against Saudi Arabia with two men less -- it's difficult," said coach Stefan Tarkovic.

"From my side, after the second red card it was just a question of the score."