Middlesbrough had keeper Mark Schwarzer to thank for keeping the deficit to one goal in the first leg of their Uefa Cup semi-final at Steaua Bucharest.
Schwarzer helped keep Boro's hopes of reaching the final alive
The Australian could do little to stop Nicolae Dica putting Steaua ahead after he turned and arrowed in a shot.
But Schwarzer pulled off a finger-tip save to send a Dorin Goian strike over before denying Dica after Stuart Parnaby's fluffed clearance.
Yakubu hit the crossbar with a header but Boro rarely threatened.
There was an intimidating atmosphere at the Ghencea Stadium, but Boro did their best early on to quell the vociferous crowd by putting the shackles on Steaua.
The Romanian side were limited to just one slight chance during a cagey start when a Dica shot over his shoulder went comfortably wide.
Boro had frustrated their opponents and had a chance to grab a vital away goal when Yakubu powered towards the home goal with runners either side of him.
Downing is well-marshalled by a dominant Steaua
But, instead of passing to the better-placed James Morrison, the striker decided to shoot and he dragged a tame effort wide.
Steaua heeded the warning and punished Boro as Dica turned and shot home from 15 yards to give them the lead with their first shot on target.
Boro responded by twice going tantalisingly close, with a Yakubu header bouncing onto the crossbar before Morrison's snapshot in a crowded penalty area was well saved by keeper Carlos Alberto.
The pace of the home side in attack was a constant threat and they quickly pinned Boro back after the break.
And the Premiership side had keeper Schwarzer to thank for keeping the score to just a goal down, the Australian pulling off a finger-tip save to deny Goian.
Schwarzer was again Boro's hero when he saved Stuart Parnaby's blushes after the right-back mistimed an attempted clearance.
Dica latched on to the loose ball but his low shot was saved low to his left by Schwarzer, who gathered at the second attempt.
A mix-up between the Boro keeper and his central defender Ugo Ehiogu almost allowed Goian another sight of goal but Matthew Bates cleared.
Peter Marin angled a strike just wide for Steaua, while Massimo Maccarone had a rare strike on goal for Boro at the other end with his deflected shot forcing Carlos to gather at the second attempt just before full-time.
Boro will be the happier with the result and will attempt to overturn the deficit in the second leg at The Riverside on 27 April.
Steaua Bucuresti: Carlos, Ogararu, Ghionea, Goian, Marin, Radoi, Bostina, Paraschiv (Lovin 86), Dica, Nicolita, Oprita (Cristea 89).
Subs Not Used: Cernea, Balan, Cristocea, Nesu, Baciu.
Booked: Dica, Paraschiv, Goian, Nicolita, Marin.
Goals: Dica 30.
Middlesbrough: Schwarzer, Parnaby, Ehiogu, Bates, Queudrue, Boateng, Rochemback, Downing, Morrison (Parlour 70), Yakubu (Maccarone 70), Hasselbaink.
Subs Not Used: Jones, Christie, Doriva, Wheater, Taylor.
Booked: Schwarzer, Parlour.
Ref: Alain Hamer (Luxembourg).