Held to a goalless draw in Slovakia a week earlier by FK AS Trencin, City had been expected to roll over their visitors in last night’s return.
Instead, the Premier League side were made to fight all the way by a visiting team who went ahead inside 91 seconds and were still on course to go through to the next stage on the away goals rule with just 10 minutes remaining.
That, though, was when Sone Aluko struck with what turned out to be the winner to send City through to the final round of qualifying and cap a memorable first night of competitive European football in Yorkshire since 2006, when Middlesbrough battled through to the UEFA Cup final.
Click on the PLAY button above to watch Richard Sutcliffe give his verdict on Hull’s first European test
Whether Hull can emulate Boro’s feat remains to be seen, they will certainly have to improve hugely on their below-par efforts across two rounds against last season’s Slovakian League runners-up.
But their name will be in today’s draw, which will take place at noon in Nyon and see Bruce’s men kept apart from European aristocracy such as Inter Milan and Celtic by virtue of being seeded.
Regardless of who City get, they will surely just be glad to still be in the competition as for long periods of last night it looked like being an inglorious exit.
Trencin’s opening goal saw to that, as did the manner in which Hull then laboured against a side who showed far more attacking intent than had been the case a week earlier in the Stadion Pod Dubnom.
That was the case from the very start, a little over a minute and a half having been played when Frantisek Kubik raced clear down the Tigers’ left before rolling a pass inside for Malec.
Unmarked and 10 yards out, the Trencin striker then instinctively hit a first-time shot that gave Allan McGregor no chance in the home goal.
Considering the Slovakians had failed to test City’s goalkeeper in last week’s first leg, the expectation was that the visitors would try and protect what they had.
The opposite, though, was the case with McGregor needing to get down smartly on nine minutes to save a Jakub Holubeck shot before the lively Haris Hajradinovic shot over as Trencin pushed forward for what would surely have been a killer second goal.
Eventually, however, the Premier League side started to exert more and more authority as Tom Huddlestone found his passing range.
Yannick Sagbo also started to use his physical strength and it was from one such flick-on that put Shane Long clear only for Milos Volesak to rush from his line and block.
Trencin’s goalkeeper had earlier denied Long a similar gilt-edged opportunity and he made it a hat-trick of stops on 24 minutes, the Irish striker again left bemoaning his luck as his close-range effort was bundled away from danger.
At that stage, it seemed like being Volesak’s night.
But then, just three minutes later, City made the breakthrough as an enticing left-wing cross from Robbie Brady allowed Ahmed Elmohamady to rise high at the back post before powering a header into the net.
It was no more than Hull had deserved and the hosts should really have been ahead at the interval only for Long to see his close-range effort blocked on the line by Volesak after a flicked header by Sagbo had found the Irishman.
Trencin had another let-off just before the hour mark when Liam Rosenior, seconds after being brought off the bench to replace the jaded Brady, shot just wide after a cross from Elmohamady had only been half-cleared.
That should have been the prelude to City forcing the pace but for the next quarter of an hour very little happened.
Bruce’s response was to bring Tom Ince and Sone Aluko off the bench and it proved an inspired move as the pair were both involved in City’s all-important second goal. Ince did the initial work, working hard to protect the ball before rolling a pass back to Elmohamady on the right flank.
He then swung over a deep cross that Snodgrass headed back across goal for Aluko to volley in from six yards out.
The 21,156 crowd, seconds earlier a picture of anxiety and nerves with their side just 10 minutes from going out on away goals, celebrated as if Aluko had won the trophy itself.
There was still time for one last scare, as Karol Mondek curled a stoppage time free-kick just wide of McGregor’s post, before Hull knew their place in the play-off round was secure.
Hull City: McGregor; Chester, Bruce (Ince 66), Davies; Elmohamady, Huddlestone, Snodgrass, Livermore, Brady (Rosenior 56); Sagbo, Long (Aluko 74). Unused substitutes: Harper, McShane, Meyler, Quinn.
FK AS Trencin: Volesak; Cogley, Ramon, Klescik, Malec; Lobotka; Kubik, Hajradinovic (Opatovsky 75), Misak (Mondek 81), Simon (Rundic 89); Holubek. Unused substitutes: Semrinec, Skovajsa, Baris.
Referee: H Nihuis (Netherlands).
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