By Gabriel TanFollow @@gabetan13
Having claimed a 2-1 win in last week's first leg in Thailand, the Thunder Castle found themselves under siege for most of Tuesday's return encounter at the Bunyodkor Stadium but were able to resist the immense pressure they were put under.
The hosts, on the other hand, will be left to rue their inability to carve out any clear-cut scoring opportunities, although they did have a legitimate penalty shout turned down and also had a goal correctly ruled out for offside.
Heading into the game aware that they definitely needed to score if they were to have a chance of progressing, Bunyodkor showed excellent initiative from the opening whistle and looked particularly dangerous down the left, where Jasur Hasanov was causing all sorts of problems with his mazy runs.
Nonetheless, his deliveries into the box failed to present his strikers any real chances in the opening proceedings, as the opposition's three-man central defence of Osmar Barba, Prathum Chuthong and Tanasak Srisai confidently dealt with any danger that crossed their path.
But in the 22nd minute, the hosts appeared set to be presented the perfect chance to break the deadlock when a freekick delivery was handled inside the area by Jirawat Makarom, only for the referee to wave away their appeals for a penalty.
Four minutes later, Bunyodkor had their first real effort on goal when Oleksandr Pyschur lined up a freekick 35 yards out from goal and unleashed a firm drive, but Sivaruck was equal to the task and smothered the shot.
Unhappy with the way his side were failing the keep hold of possession, Buriram coach Scott Cooper decided to bring on Carmelo Gonzalez for Suriya Domtaisong even before the half-hour mark, and the switch did go some way in addressing the problem.
With the Spaniard on, the Thunder Castle began to show more fluency in the attacking third but it was their opponents who continued to look the more likely to score. Four minutes before the break, Hasanov broke free again down the left and cut the ball back to Turaev, whose miscued shot looked destined to find Igor Taran until Prathum's timely clearance.
However, just before the break, it was the visitors who came close to breaking the deadlock after a dangerous freekick from Theerathon Bunmathan was spilled by Murod Zukhurov, who did well to recover in time and block Osmar's follow-up effort.
Having completed half the job by keeping their opponents at bay for 45 minutes, Buriram then looked to have shot themselves in the foot when they went to sleep during a corner, allowing Pyschur to meet the delivery and prod the ball past Sivaruck from six yards out.
Thankfully for them, the linesman's flag came to their rescue but apart from that one chance, Bunyodkor continued to fail in their bid to find the final delivery inside the area, with Sivaruck standing firm between the sticks.
At the other end of the field, Carmelo was continuing to prove a useful outlet and he managed to break free inside the area in the 62nd minute, but Artyom Filiposyan weighed in with a vital interception to prevent the Spaniard's cross from reaching a team-mate.
Still, as the game entered its closing stages, Buriram began to look increasingly content to sit back and defend and it nearly cost them in the 77th minute after Oleg Zoteev's left-wing cross was flicked on by Lutfulla Turaev straight to Kamoliddin Murzoev, but the 26-year-old took too long to bring the ball down and could only blaze over under pressure from the recovering Prathum.
Three minutes later, Murzoev wasted another excellent chance when he sent a header over from eight yards after yet another brilliant delivery from Hasanov.
With Bunyodkor pushing more and more men forward, gaps started to appear in their defence and Zukhurov had to produce a vital save in the 82nd minute to tip an effort by Adisak Kraisorn narrowly wide, after the Thailand Under-23 international raced onto a lovely through-pass by Anawin Jujeen and sent the ball towards goal.
As the clock ticked over into injury-time, Buriram had one final chance to kill the game off when they hit the hosts on the counter and Carmelo was left with a clear path at goal, only for him to slip at the vital moment when he was entering the area.
But in the end, it was purely academic as the Thai outfit held on to book their place in the last eight of Asia's premier club competition, keeping alive their hopes of emulating BEC Tero Sasana's run to the final back in 2003.
Bunyodkor: Murod Zukhurov, Akmal Shorahmedov, Artyom Filiposyan, Hayrulla Karimov, Sakhob Juraev (Oleg Zoteev 55'), Jovlon Ibrokhimov, Marko Blazic (Alibobo Rakhmatullaev 70'), Lutfulla Turaev, Oleksandr Pyschur, Jasur Hasanov, Igor Taran (Kamoliddin Murzoev 66').
Buriram United: Sivaruck Tedsungnoen, Tanasak Srisai, Osmar Barba, Prathum Chuthong, Suree Sukha, Surat Sukha, Jirawat Makarom (Anawin Jujeen 72'), Theerathon Bunmathan, Suriya Domtaisong (Carmelo Gonzalez 28'), Suchao Nutnum, Kai Hirano (Adisak Kraisorn 54').
Image courtesy of Buriram United FC