Lionel Messi and Cristiano Ronaldo will be reunited for the first time since the latter's move to Italy in 2018 when Barcelona host Juventus in Champions League on Tuesday, but what is their history like?
Both sides have already qualified for the next stage of the Champions League and Ronald Koeman's men need to avoid losing by at least two goals to clinch top spot in Group G.
Messi missed the trips to Dynamo Kyiv and Ferencvaros, but is set to return for what would be his first match against Cristiano Ronaldo since the Portuguese left Real Madrid for Juventus in 2018.
They top the charts in categories across the board, but how do the two superstars compare and what have they been up to since they last saw each other?
The overall history
Ronaldo and Messi have faced each other in 35 games between club (33) and country (2), with both international meetings being friendlies. It is one win apiece too - Argentina won 2-1 in February 2011, with both Ronaldo and Messi scoring. The other was in November 2014 with a Portugal 1-0 win.
Of course, their most regular clash came in El Clasico, with only three of their 33 club games being played while Ronaldo was at Manchester United. The other 30 were between Real Madrid and Barcelona. Messi has been victorious in 16 of their 35 meetings, Ronaldo in ten, with nine draws.
Unsurprisingly, both players became the El Clasico top scorers for their respective teams. Messi has scored 26 goals and Ronaldo did so 18 times, level with Real Madrid legend Alfredo Di Stefano.
In terms of overall goals, Ronaldo has scored 648 times since his professional debut for Sporting Lisbon in 861 club games. Messi has scored 641 club goals, all for Barcelona in 744 games, and both are the all-time top scorers for Real Madrid and Barcelona respectively.
Ronaldo missed out in the reverse fixture in October after testing positive for coronavirus. Barcelona were 2-0 winners at the Juventus Stadium with Messi scoring a 90th-minute penalty after Ousmane Dembele's early opener.
Ronaldo vs Messi in the Champions League
Ronaldo and Messi have faced each other five times in the Champions League, three times when the Portuguese played for Manchester United and twice for Real Madrid. They have not met in European competition since the El Clasico semi-final in the 2010/2011 season.
Messi has the upper hand in these fixtures (W2 D2) with only one Ronaldo victory, coming in the 2007/08 semi-final second leg at Old Trafford. But incredibly, the Juventus striker has never scored against a team including Messi in the Champions League, with the Argentine netting three times, including in the 2009 final in Rome.
Both are also the top scorers in European Cup/Champions League history, being the only players to reach 100 goals in the competition. Ronaldo was the first to surpass the century, netting 132 times, with Messi scoring 118 goals. Both are equalled for Champions League hat-tricks (8), as well as trebles in the top five European leagues (36).
How have they fared since Ronaldo's move to Italy?
Ronaldo has continued to play a key role at Juventus. He scored 26 goals in 43 appearances in all competitions in the 2018/19 season and bettered this with 37 goals in 46 appearances last season. He has scored eight goals in six Serie A games this term, even with a self-isolation period. The Portuguese has also won the league title in both seasons, although only by one point in a disjointed 2019/20 campaign.
However, he has already played under three managers in Italy. Ronaldo was signed under Massimiliano Allegri, before Maurizio Sarri arrived last summer. He was then replaced in August by Juventus legend Andrea Pirlo, whose only loss this season was against Barcelona six weeks ago.
He was only the third Juventus manager after Marcello Lippi and Fabio Capello to win his first away game in the Champions League with a 2-0 win against Dynamo Kiev. However, Juventus have stuttered in Serie A this season, winning five times and drawing the other five, and are currently fourth with 20 points, six behind leaders AC Milan.
Messi's last two seasons have been far more fractious. He sent shockwaves around the world in August when he announced his desire to leave Barcelona, increasingly unhappy with matters on and off the field. After much media speculation and attention, Messi soon decided to stay at the club for the 2020/21 season.
He has already scored seven goals in 13 Barcelona appearances this season - including in his last three Champions League appearances - having netted 31 goals in 44 games in all competitions last term. Barcelona last lifted the La Liga title in the 2018/19 season, when Messi scored an incredible 36 goals in 34 league games.
The Argentine has also had three managers. Ernesto Valverde led Barcelona to the La Liga trophy before being dismissed in January. Quique Setien was appointed in his place before Ronald Koeman arrived but he has already lost four La Liga games this season, including a shock 2-1 loss to Cadiz on Saturday.
Barcelona forward Dembele - who scored the opening goal in the reverse fixture - suffered a hamstring injury at the weekend and will not feature.
The France international joins Ansu Fati, Gerard Pique and Sergi Roberto on the treatment table, while defender Samuel Umtiti remains a doubt with a knee problem despite training.
Juventus are set to be without Merih Demiral and Giorgio Chiellini, but Pirlo confirmed that Gianluigi Buffon is fit and could feature. Alvaro Morata could also find himself involved as he is currently serving a domestic suspension.
What the managers said
Barcelona manager Ronald Koeman said: "Our goal is always to win by playing well. We intend to finish first in the group, we have a good advantage and good chances. We've made many mistakes that have cost us points, we need to keep a better balance and improve our effectiveness.
"We aren't just thinking about Cristiano, who is nevertheless a great champion, who always battles and scores. We're thinking about tomorrow's great match: we'll have to defend well and keep possession of the ball.
"It will be fantastic to see two great champions like Messi and Cristiano, the best of the last 15 years. It's not nice to say who is the best, I admire both, because they are incredible and have given us great evenings."
Juventus manager Andrea Pirlo: "This match is especially important for our growth and self-esteem. Coming first is important, but what we put in on the pitch is even more important.
"Compared to the first game, we need to improve the non-possession phase and be closer to the midfield and defensive lines. In the derby [against Torino], we had a completely different attitude between the first and second half, winning all the duels. This is the attitude that is part of Juve's DNA and must never be missing.
"Koeman is right: it would be wrong to say who is better between Messi and Cristiano. They are two phenomenons that put-on spectacles for millions of fans. We just have to thank them.
"It's a period where many great players struggle, it's normal. The great players have had little time to rest and were immediately busy with their national teams. Everything will be more normal after Christmas. If Cristiano is in good form, it means that he is in the right place at the right time and we are good at giving him the ball."
- Barcelona have gone unbeaten in their last four meetings with Juventus in the UEFA Champions League (W2 D2), winning two of the three games in this run that occurred in the group stage (D1).
- Juventus' only away victory against Barcelona in the UEFA Champions League came back in April 2003 (2-1), having failed to win either of their two trips there in the competition since (D1 L1) - 0-0 in 2016-17 and 0-3 in 2017-18.
- Juventus haven't scored in any of their last four meetings with Barcelona in the UEFA Champions League (D2 L2). Since Giorgio Chiellini's goal in a 3-0 win in April 2017, they have gone 395 minutes of play without scoring against the Spanish side in the competition.
- Barcelona have won all five of their group stages matches this season, and could record the eighth instance of a side winning 6/6 games in a single group stage in the Champions League. Barcelona themselves account for one of the previous seven instances, back in 2002-03 under Louis van Gaal (1st group stage in that case).
- Barcelona forward Martin Braithwaite has scored in both of his UEFA Champions League starts for the club - the only player to score in each of his first three starts for Barcelona in the competition is Gabri in 1999-2000.