Ten-man Aberdeen dropped into the Conference League as a "game-changing" red card and FCSB penalty turned the Europa League play-off tie in favour of the eventually comfortable Romanian champions.

The already-cautioned Alexander Jensen was caught scrambling in his own box as David Miculescu snuck in behind to scoop up a searching ball, which, on review, struck the hand of the Aberdeen defender.

After a lengthy delay it was deemed a second bookable offence and a penalty – though it appeared harsh given the close proximity and speed the Dane was dashing back at.

"It's not an excuse but [the penalty] is a tough one and of course, it changes the dynamic of the game," Aberdeen manager Jimmy Thelin told BBC Scotland.

"Over the two games, we get punished but we can't punish them, that's the difference."

Captain Darius Olaru struck from the spot and sucked the life out of what had been a promising showing from the Dons.

Having recovered from two goals down in last week's first leg at Pittodrie, Thelin's side started brightly in Bucharest and seemed the more likely to take the lead in the tie.

Ester Sokler, whose late header ensured the Dons came into the second leg level, should have scored inside two minutes but his close-range effort was agonisingly weak.

Even so early on, there was a sense that chance would haunt Aberdeen. And it did.

The competitiveness of the first half was ceased in that single decision, and though FCSB were under no threat in the second half, Adrian Sut's superb strike squashed any lingering home nerves before Olaru added a deflected third.

Aberdeen will now play in Europe's third-tier competition – and will learn their opponents in tomorrow's draw at 12:45 (BST) – while FCSB will enjoy the Europa League.

That's a sore one for Aberdeen.

Up until the cruel call minutes before the break, Thelin ought to have been delighted with his team's showing.

The clamour for a Dante Polvara start had hit its peak after last week's cracking cameo, and the American showed why the calls were justified.

Simply put, Aberdeen are a better side with the American in it.

A calming influence with an eye for a perfect pass, the towering midfielder had a chance of his own to open the scoring when he rose at the back post.

That was one of many highlights in an encouraging 40 minutes or so for Aberdeen. That's what they have to hold on to not only domestically, but in their Conference League campaign.

As is the cliché, though, it's fine margins at this level.

FCSB didn't have to work hard for their win. For a side who came into the tie with super confidence, they didn't qualify "without problems" as their owner Gigi Becali predicted.

Aberdeen manager Jimmy Thelin: "In these situations with the skill of the opponents, when you make a mistake, they have enough quality to hurt you. In turn, we have to find the calmness and create more in our own situations.

"You have to move on quick and be ready for Sunday's game and that's also my job, to get the players in that direction because that's how you grow as a person, as a player and you take responsibility."

Aberdeen defender Mats Knoester: "I think that was a massive hit for us, but then the way we respond, we should do better and stay in the game longer.

"You know you're going to get one or two chances and then it's still possible, you know? So yeah, disappointment is the logical feeling after.

"I haven't seen it back yet, but from what I saw in the game, it looked like quite natural movement."

Aberdeen will learn of their Conference League opponents in Friday's draw at 12:45 (BST).

Having taken advantage of the option to postpone their league game last weekend against Dundee United, the Dons return to Scottish Premiership action on Sunday at home to Falkirk (15:00).