Manchester United will come up against an old foe when they take on Atletico Madrid in the Champions League tonight.
Former Liverpool striker Luis Suarez became Public Enemy No.1 with United fans after the Football Association found him guilty of racially abusing Patrice Evra during a game at Anfield in 2011, for which he was hit with an eight-game ban and £40,000 FA fine.
Suarez will come face-to-face with United again this evening, with Atletico hosting United in the first leg of their Champions League last-16 tie in the Wanda Metropolitano Stadium.
With Suarez set to be a key protagonist in the tie, who better to offer an expert assessment of the key battles in the contest than former Atletico striker Fernando Torres, who made way for Suarez at Liverpool in 2011.
Torres, currently boss of Atletico's Under-19s team, was also a thorn in United's side during his time in England, scoring four times against them in the Premier League for Liverpool and Chelsea.
Now 37, Torres won 110 caps for Spain, scoring 38 goals in a glittering international career that saw him win the World Cup and two European Championships.
At club level, he won the Champions League, FA Cup and Europa League with Chelsea, also winning the latter with Atletico in his second spell at the LaLiga club, notching 263 goals from 768 career club appearances.
Having won the Champions League with Chelsea, Torres knows exactly what is required to lift the famous trophy.
Although United and Atletico may not be among the favourites to go all the way and do just that, tonight's encounter promises to be a fascinating tie with some absorbing individual battles.
Have Your Say! Will Atletico or Man Utd go through? Make your prediction here.
Will Real Madrid icon Cristiano Ronaldo shine on his return to the Spanish capital and will Jadon Sancho continue his impressive recent form for United, which has seen him register two goals and two assists this month?
Can Paul Pobga build on his impressive form since his return from injury and can United skipper Harry Maguire, impressive in Sunday's epic 4-2 win over Leeds, maintain that focus against superior opposition?
Torres answers these questions and more, after Mirror Sport asked him to name and explain the five key areas, which will decide which of the sides will emerge triumphant over two legs and progress to the quarter final.
Jan Oblak v Cristiano Ronaldo
Oblak has been honest - he has not been playing at his best this season. But he is still one of the best goalkeepers in the world.
Maybe there is not a bigger game player in the world than Ronaldo and these are the nights that he loves.
Luis Suarez v Raphael Varane
Due to injuries, I think Suarez will play. He has not been in his best form, but the world knows what Luis Suarez is capable of and playing Manchester United will be a big incentive for him.
Varane knows all about the Champions League and his experience will be important.
Joao Felix v Harry Maguire
He can cause a lot of problems for Maguire and make it a very long night for him.
This is going to be a game where Maguire will need to use all of his experience – because in terms of agility and speed, Felix is ahead.
Koke v Bruno Fernandes
Koke is one of the best passers of the ball in Spain - his vision is excellent.
Bruno has the goal record of a striker and Manchester United need that at the moment, with their strikers not scoring as many goals as the coach would like.
Thomas Lemar v Paul Pogba
These two players have so much talent – when they are at the top of their game they can make such a big difference.
Both could find more consistency – but if they play at their highest level then they can both dictate games.
