Singapore's Tampines Rovers got another reminder of the harsh realities of life in the fast lane of the Asian Champions League after suffering an embarrassing 9-0 defeat to Jeonbuk Hyundai Motors on Thursday.
Gustavo grabbed four goals and Modou Barrow scored thrice as the South Koreans moved within touching distance of a spot in the last-16 of the tournament they have won two times.
Conversely for the Rovers it was as good as curtains for them in a format where only the group winners are guaranteed progress into the knockouts after the AFC expanded the tournament to 10 groups this year.
Jeonbuk were up and away in the sixth minute at the Lokomotiv Stadium in Tashkent with Gambia midfielder Barrow tapping in from close after combining well with Brazilian striker Gustavo in a move that originated in the midfield.
Gustavo turned the provider in the 14th minute scoring from a great pass by Ryu Jae-moon and then grabbed his second barely a minute later with another cracking shot past goalkeeper Muhammad Syazwan.
Kim Seung-dae made it 4-0 in the 35th minute before Jeonbuk added five more in the second half with Gustavo and Barrow sealing their hat-tricks and giving their team a healthy plus-10 goal difference in Group H after just three matches.
Also in Group H, Gamba Osaka were forced to share points with Thailand's Chiangrai United who snatched a 1-1 draw in second-half stoppage time.
Brazilian Leandro Pereira had put Gamba ahead in the 47th minute but their hopes of bagging a crucial win were dashed in the fourth minute of added time as fellow countryman striker Rosimar Amancio, known simply as Bill, scoring from close with the last foray of the match.
Gamba are second behind Jeonbuk with five points but Chiangrai are also in the hunt with four, hoping to make the cut as one of the best second-placed teams
Earlier, Nagoya Grampus eased past Ratchaburi 3-0 and Pohang Steelers accounted for Johor Darul Ta'zim in Group G as Southeast Asian sides continued to struggle.
Ratchaburi succeeded in keeping Grampus at bay in the first half but their resistance crumbled after the break with Brazilian striker Mateus finding himself in great position to score in the 51st minute after a cross by Kazuki Nagasawa took a deflection and fell in his path.
Yoichiro Kakitani and Ryogo Yamasaki put the outcome of the match beyond doubt with a goal each within six minutes as Nagoya again kept a clean slate and almost assured themselves of a spot in the round of 16 with their fourth win in as many matches.
The Steelers meanwhile notched their third win in four matches to also stay in contention as they scored twice in the first half against Malaysia’s Johor.
After seeing several scoring opportunities go to waste, Lee Seung-mo broke the deadlock in the 33rd minute taking advantage of a measured pass from Go Young-joon.
The Johor defence was caught napping again four minutes later as captain Kang Sang-woo struck with an easy finish after a defence-splitting pass from Ukrainian Borys Tashchy.