Hanoi T&T did their chances of winning the V-League championship a world of good with a 2-0 away win over another strong contender, Binh Duong, at the Go Dau Stadium on Sunday.
The hosts stepped up the tempo right at the beginning of the 21st round match as they strove to keep alive their title hopes this season.
However, the 2007-08 champs and 2009 runners-up were upset by a sharp counterattack from the capital city side.
Referee Vo Quang Vinh contributed to Hanoi T&T's opener when he was deceived by Vo Duy Nam's dive in Binh Duong's penalty area.
The referee pointed to the penalty spot while TV replays showed that Binh Duong custodian Minh Quang hadn't touched Duy Nam.
Striker Cao Sy Cuong found the net from the spot with no fuss, and Hanoi T&T were one up after nine minutes.
The goal further boosted Hanoi T&T players's spirits and they looked more dangerous with their counterattack strategy. Just before the break, Ngoc Duy found the net to put them two up.
Binh Duong players never recovered from the double-strike in the first half, and despite having four strikers up front in the second half, they failed to dent the Hanoi team's defence.
Anh Duc, Vietnamese Brazilian Huynh Kesley, South African and Brazilian strikers Philani and Elendino De Jesus all failed to hit the target.
With just five rounds remaining, Hanoi T&T with 40 points are five points clear of third-placed Binh Duong and second-placed Dong Thap, who lost 0-2 to Nghe An.
Reigning champs Da Nang with 32 points look to have given up after a 1-1 home tie with Ninh Binh at Chi Lang Stadium.
Nam Dinh, with just 12 points, are certain to be relegated to the second-tier First Division while Navibank Saigon with 18 points are hovering the relegation zone.
The 2010 season can look forward to a tense and exciting end as at least five teams including 2003-04 champs Hoang Anh Gia Lai and 2005-06 champs Dong Tam Long An are in danger of facing a play-off match.
According to the rules, the third team from the bottom will play off against the third best team in the second-tire First Division for a place in the V-League's next season. The bottom two teams in the V-League are relegated, while the top two teams in the First Division move up to the V-League the next season.