In this photo provided by the Asian Football Confederation (AFC), Kim Bo-kyung of Jeonbuk Hyundai Motors celebrates his goal against Yokohama F. Marinos during the clubs' Group H match at the AFC Champions League at Thong Nhat Stadium in Ho Chi Minh City on Sunday. (AFC)

And then there were two.

Two out of four South Korean teams have reached the knockout stage of the Asian Football Confederation (AFC) Champions League, the top annual club tournament in the region. Jeonbuk Hyundai Motors and Daegu FC are in, while Ulsan Hyundai FC and Jeonnam Dragons have been sent packing.

Jeonbuk became the first to do so by beating Sydney FC 3-2 last Thursday in their penultimate Group H match in Ho Chi Minh City. They closed out the preliminary phase with a 1-1 draw against Yokohama F. Marinos on Sunday in Vietnam.

Yokohama won the group with 13 points and Jeonbuk ended up one point back. They grabbed their knockout berth by finishing as the top runners-up in the East Region.

There were 10 groups of four in this year's tournament. The 10 group winners earned automatic berths in the round of 16, joined by the top three runners-up from each of the East and West regions. Groups A to E had teams from the West Region, with countries including Qatar, Saudi Arabia, Iran and Iraq, and Groups F to J featured clubs from the East Region, and among its countries were South Korea, Japan, China and Australia.

In the round of 16, scheduled to be played in August, Jeonbuk will run into Daegu FC. This means only one K League club will have a chance to win the AFC title.

"We know each other really well, so we'll have to prepare for the match the best we can," Jeonbuk head coach Kim Sang-sik said. "We don't know where the round of 16 match will take place yet, and we'll have to make adjustments no matter what the circumstances."

Daegu FC won Group F by beating Lion City Sailors 2-1 Saturday at Buriram Stadium in Buriram, Thailand. The match featured a lengthy rain delay, and Zeca converted an 81st-minute penalty to send Daegu to the knockouts for the second straight year.

Daegu FC head coach Alexandre Gama praised his players for their mental toughness, as they completed the rally following the rain delay.

"We were playing well before giving up the first goal (in the first half), and our players never gave up," Gama said. "We mounted the comeback in the second half by putting more pressure on our opponents. We've played a lot of good matches here, but the most important thing is we have built connections with one another. We will try to build on this momentum back in Korea."

Two other South Korean teams, Ulsan Hyundai FC and Jeonnam Dragons, were sent packing.

Ulsan, the 2020 AFC champion and leaders of the K League 1 this season, suffered a 2-1 loss to Johor Darul Ta'zim in their Group I match Saturday in Johor Bahru, Malaysia. Park Yong-woo's own goal in the dying moments sealed Ulsan's fate, as they will be missing out on the knockouts at the AFC tournament for the first time since 2017.

Ulsan finished third in their group with 10 points, with two losses to Johor, considered underdogs against Ulsan, stinging particularly hard.

Ulsan head coach Hong Myung-bo said his players had given their best and they will learn from this experience.

"In order to take the next step, our team had to overcome adversity like this," Hong said. "We weren't able to do it, and as a result, we were eliminated. I believe there are a lot of lessons from this competition that can help us grow when we return to Korea."

Jeonnam, the first K League 2 club to compete at an AFC Champions League, played BG Pathum United to a scoreless draw in Group G action on Saturday at Pathum Thani Stadium in Pathum Thani, Thailand. Jeonnam had to win that match and get help from others to squeeze into the knockouts. Instead, they finished in third place in the group with eight points.

Jeon Kyeong-joon, head coach for Jeonnam, said he takes all the responsibility for not putting the club past the group stage.

"It was an honor to play in this tournament and I am disappointed that we didn't get the result we wanted," Jeon said. "If we can make it back here, hopefully we'll be able to go deeper into the tournament, the round of 16 and even the quarterfinals."

The knockout stage for the East Region will begin in August. The championship final, played over two legs, will be in February 2023. (Yonhap)