Leeds Carnegie were forced to dig deep and hit back from 6-5 down at half-time to see off the challenge of Romanian amateurs Bucharest.
In truth, the home side would have been well in control at the interval if they had taken just one or two of their chances but too often players were guilty of forcing passes and unforced errors.
The coaching team of Andy Key and Neil Back named a strong team which included England internationals Steve Thompson and Hendre Fourie and fit-again winger Michael Stephenson as they looked to build some confidence and momentum.
Leeds dominated the early exchanges and referee Carlo Damasco was left with little option but to continually penalise the visitors as they loitered offside attempting to slowdown the home forays.
It seemed inevitable Leeds would score after a barrage of attacks on the Oaks line, but Alfie To'oala was penalised for going to ground as he came to support a ruck and the chance went begging.
Leeds had another great opportunity on 11 minutes when they stole
possession and Danny Paul broke 30 metres up field, but his final pass came off Stephenson and bounced forward.
They were made to pay three minutes later when, remarkably, Bucharest took the lead – Florin Vlaicu landing a penalty from just inside the home half.
Carnegie continued to dominate possession but on three more occasions they were guilty of forcing the pass and poor execution saw the ball knocked on.
Bucharest, in contrast, grew in confidence and doubled their lead when Leeds were penalised for holding on in the tackle 22 metres out, Vlaicu booting his second penalty.
The home side finally got off the mark on 34 minutes when Luther Burrell ran hard and direct at the Bucharest line before offloading to Leigh Hinton who put Semi Tadulala away in the corner. Hinton missed the touchline conversion.
Leeds' day though was going from bad to worse with injury blows either side of that touchdown. First, Paul had to helped from the field with a leg injury and he was followed soon afterwards by Fourie, though the latter looked pre-cautionary.
Hinton missed a penalty with the last kick of the half to leave the home side trailing at the break.
Bucharest could sense the frustration that Leeds were obviously feeling and threw everything at the Aviva Premiership outfit in the opening exchanges of the second period.
However, Leeds defended well and finally got the breakthrough when skipper Marco Wentzel finished off a good spell of pressure on the hour mark. Christian Lewis-Pratt added the conversion to make it 12-6.
That seemed to settle Carnegie and in the final quarter they wrapped up the bonus point with two further tries.
The first came from replacement prop Miguel Alonso who made the most of some good play by the forward pack, in particular James Craig, before he rumbled over.
The final touchdown saw the ball moved 80 metres down field in a matter of seconds. Phil Nilsen broke away from his own line before a clever kick by Lewis-Pratt put the Oaks full-back under pressure and when he attempted to offload as he was tackled by Hinton, the ball flew loose and Burrell was on hand to snatch up the interception and go over for the try.
Lewis-Pratt converted both tries to end the scoring.
Leeds Carnegie: Hinton, Stephenson, Tincknell, Burrell, Tadulala, Lewis-Pratt, Fury, Hardy, Thompson, Denman, Craig, Wentzel, To'oala, Fourie, Paul. Replacements: Nilsen, Alonso, Gomez, Oakley, Rowan, Black, MacKay, O. Denton.
Bucharest: Botezatu, Nicolae, Cazan, Dascalu, Lemnaru, Vlaicu, Surugiu,
Tamba, Beca, Badalicescu, Popirlan, Drenceanu, Macovei, Lucaci, Carpo. Replacements: Zebega, Nere, Maris, Burcea, Ianus, Calafeteanu, Dumbrava, Gal Minya.
Referee: Carlo Damasco (Italy).