London (AFP) - Manchester United booked their place in the Europa League last 16 with a 2-0 win at Romanian side FCSB, while troubled Tottenham turned to their young guns to advance via a top-eight finish on Thursday.

Diogo Dalot and Kobbie Mainoo scored for United in the second half of their final league phase fixture at the National Arena in Bucharest.

In north London, under-pressure Tottenham boss Ange Postecoglou was relieved to see Dane Scarlett, Damola Ajayi and Mikey Moore kill off Swedish minnows Elfsborg with their first goals for the club in a 3-0 victory.

United, unbeaten in eight games in the tournament, finished in third place and Tottenham came fourth, ensuring the Premier League clubs both avoided the Europa League play-off round.

The top eight automatically progress to the last 16, where they will be seeded against the winners of eight two-leg knockout play-off ties featuring the clubs ranked from ninth to 24th.

Ruben Amorim’s side extended their recent improvement to one defeat in seven games in all competitions with a third successive victory for the first time this season.

United were patchy in the first half but Amorim sent on Amad Diallo and Alejandro Garnacho at the break and they helped turn the tide.

United finally took the lead in the 60th minute when Mainoo guided a dangerous low cross into the six-yard box and Dalot timed his run to slot home with ease.

Daniel Birligea almost hauled FCSB level immediately with a thunderous strike that nearly crossed the line after hitting the bar.

But Mainoo’s composed finish from Garnacho’s cutback in the 68th minute put the result beyond doubt.

“More than the win is to have time to train and have time to recover the players,” Amorim said of United avoiding the play-offs.

“The lads did a good job but we have to understand the opponent is not with all due respect the same level as the Premier League. We want to improve a lot with the way we play.”

- Spurs kids lift the gloom -

At the Tottenham Hotspur Stadium, it took three of the club’s promising academy graduates to lift the gloom.

Tottenham are languishing in 15th place in the Premier League, eight points above the relegation zone after winning just one of their past 11 top-flight matches.

Last weekend’s defeat against fellow strugglers Leicester condemned Tottenham to their longest winless streak in the league since 2008.

Postecoglou admitted he is not sure of his job status after fans jeered the team and called for chairman Daniel Levy to quit during the Leicester debacle.

Tottenham lost centre-back Radu Dragusin to a knee problem as their injury woes mounted in the second half, but his replacement Scarlett ended Elfsborg’s resistance in the 70th minute.

Dejan Kulusevski’s cross picked out Scarlett and the 20-year-old striker headed home, just days after returning from a loan spell at second-tier Oxford.

Ajayi, 19, had only been on the pitch four minutes when he converted Scarlett’s pass to mark his debut in style in the 84th minute, and there was still time for Moore, 17, to strike in stoppage time.

“It was ‘Made in Tottenham’. It’s brilliant, the whole academy should be proud,” Postecoglou said.

“We needed something tonight and the young lads stepped up. I’m sure they won’t sleep because they are pretty excited.”

Scottish side Rangers made it to the last 16 after climbing to eighth place with a 2-1 win against Belgium’s Union Saint-Gilloise at Ibrox.

Nicolas Raskin and Vaclav Cerny scored for Rangers before Kevin Mac Allister’s reply set up a tense finale.

Jose Mourinho’s Fenerbahce scraped into the play-offs, finishing in 24th place – above Braga on goal difference – after a 2-2 draw at Midtjylland.

Lazio came top of the league phase despite a 1-0 defeat at Braga, while Athletic Bilbao beat Viktoria Plzen 3-1 to secure second place.

Fifth-placed Eintracht Frankfurt, sixth-placed Lyon and seventh-placed Olympiakos comprise the rest of the top eight.

Roma secured a play-off place, beating Frankfurt 2-0 through goals from Angelino and Eldor Shomurodov.