Pohang Steelers, the K-League reigning champions, lead South Korea's top tier and will travel to second-placed Jeonbuk Motors on Tuesday for the first leg of their ACL last-16 tie.
In all, three of the eight round-of-16 clashes will involve two clubs from the same country with Saudi Arabian pair Al Ittihad and Al Shabab facing off, while Al Jazira will take fellow Emirati side Al Ain for a spot in the quarter-finals.
Jeonbuk and Pohang have already met once this season with the Steelers winning 3-1 in the second round of the 2014 K-League season.
Kim Seung-Dae, who scored the third goal in that victory in March, will be the Steelers' target up front with the 23-year-old striker having already notched 10 goals in all competitions this season, including four in the ACL.
Kim is in red-hot form, with eight goals in as many games in all comps.
Pohang have not lost since mid-March, while Jeonbuk's form has been less consistent with two defeats and a draw in their past seven matches.
Jeonbuk edged into the ACL knockout stages with a scoreless draw against Melbourne Victory to take second spot in Group G, while the Steelers comfortably topped Group E, four points clear of second-placed Cerezo Osaka.
Al Shabab will travel to Jeddah for their first leg against Al Ittihad on Tuesday in far better form than their fellow Saudi club.
Ammar Souayah's Shabab side claimed five wins and a draw to finish first in Group A, while Ittihad finished second in Group C but are winless in three games in all competitions.
ACL top-scorers Al Ain and Al Jazira will face off for the second time in seven days, after a 2-2 draw in the Arabian Gulf League on Thursday.
Asamoah Gyan struck twice in the first half to give Ain a 2-0 lead at the break but Felipe Caicedo and Ali Ahmed Mabkhout struck in the final half-hour to secure a draw for Jazira.
Gyan has been the key man behind Ain's continental scoring prowess - they scored 14 goals in the group stage - with the Ghanaian striker scoring half their goals in Asia.
Reigning ACL champions Guangzhou Evergrande will take on Cerezo in the round of 16, while J.League title-holders Sanfrecce Hiroshima will host Western Sydney Wanderers on Wednesday, just three days after the latter plays in the A-League grand final.
In other round-of-16 first legs, Kawasaki Frontale will welcome FC Seoul to Japan, Al Hilal will travel to Uzbekistan to play Bunyodkor and Al Sadd take on Foolad.
