Manchester United are one win away from securing a second trophy in Jose Mourinho's first season and qualifying for the Champions League next season.
While they made hard work of it, United, eventually, saw off the challenge from Celta Vigo, topping the Spanish side 2-1 on aggregate, after the second leg at Old Trafford finished 1-1, and with ten men each on the pitch, in the Europa League semifinal.
In a sometimes ill-tempered semifinal second leg, Manchester United took an early lead through Marouane Fellaini, who made it 1-0 on the night and 2-0 on aggregate with a nice header.
However, with United failing to find the insurance goal, Celta Vigo stayed in the tie, even more so when Facundo Roncaglia scored in the 85th minute.
One more goal for Celta Vigo and they would have gone through on the away goals rule, and that tension showed when Manchester United and Celta players got into a bit of a tussle, with Eric Bailly and the goalscorer Roncaglia seeing red.
With both sides down to ten men, it got a little more tense, and United's hopes of qualifying for the Champions League next season – as Mourinho has said several times, that is the priority, more than winning another title – nearly ended in the last kick of the game.
Claudio Beauvue decided to pass to John Guidetti, when he would have been better off shooting, and when the former Manchester City man received the ball, he hesitated too much, allowing a really good chance to go.
Mourinho, the United players and the Old Trafford fans breathed a huge sigh of relief and as after the referee blew the final whistle, the celebrations began.
"They (Celta Vigo) did very well, they gave us a very difficult second half," Mourinho said. "So we had to suffer until the end and everything was open until the last second. The boys didn't play a phenomenal match but they fought, they gave everything they had to give and I'm really pleased for them because 14 matches and we are in the final so it's good."
Manchester United will now meet Ajax in the final of the Europa League, with the odds looking pretty good for the English Premier League side, considering Mourinho has never lost to the Dutch team in his career.
"First of all two monsters – the history of Manchester United and the history of Ajax is amazing," Mourinho added of the Europa League final. "But for us [if we win] it's a trophy and the Champions League for next season.
"Finals are always fun, and the Europa League is a big, beautiful competition."
Ajax were made to sweat for their place in the final, with their 4-1 first leg win coming in really handy in the end. Lyon, with nothing to lose, gave Ajax a real scare, but the 3-1 victory in France, studded by a brace from Alexandre Lacazette, proved to be one goal short of what was required, as the Dutch side went through 5-4 on aggregate.