Atletico Madrid will look to take advantage of what has been a difficult couple of weeks for Barcelona when the Spanish rivals meet for the second leg of their Champions League quarter-final at the Vicente Calderon on Wednesday night.
Barcelona have lost their last two in La Liga to blow the title race wide open, but they will enter this week's match with a 2-1 advantage from the first leg last week and having won their last seven against Atletico in all competitions.
Atletico
If Atletico are to progress into the semi-finals of the Champions League this season, they will need to do something that they have not managed since April 2014 - beat Barcelona.
That victory, however, came in the quarter-finals of the 2013-14 Champions League, when a strike from Koke saw Diego Simeone's side overcome Barcelona to make the semi-finals. Since then, they have lost seven times against the Catalan giants - including on all three occasions that the two sides have clashed this season.
Barcelona have recorded 2-1 victories in both La Liga matches and as mentioned, were also 2-1 winners at Camp Nou in the first leg. Fernando Torres sent Atletico into a 25th-minute lead last week, but the striker then saw red 10 minutes later, which helped Barcelona turn it around courtesy of a second-half double from Luis Suarez.
Barcelona might be the more experienced team at this stage of the competition, but this is the third season running that Atletico have reached the quarter-finals of the Champions League and they have faced Spanish opposition on both occasions - losing to Real Madrid in the last eight 12 months ago.
Atletico also boast an excellent home record in Europe, having lost just two of their last 28 at the Vicente Calderon - recording 23 victories in the process. Should they reach the semi-finals this season, it would be the fifth time that they have progressed to the final four and they have still managed to advance in 11 of the 20 UEFA competition ties where they lost the first leg away from home.
Atletico's record of 12 goals in nine games is the lowest return of any Champions League quarter-finalist this season, but their challenge has once again been built on an excellent defence. Incredibly, the capital outfit have conceded in just one of their last 11 Champions League matches at the Vicente Calderon.
Simeone's side have also managed to close the gap at the top of La Liga to just three points courtesy of a 3-1 victory over Espanyol at the weekend. Back-to-back defeats for Barcelona have thrown the title race wide open and it would be some story if Atletico could eliminate Barcelona from this competition and also beat them to the punch in La Liga.
Recent form: DWWDWL
Recent form (all competitions): WWLWLW
Barcelona
When Barcelona entered April with their 39-game unbeaten run intact, Luis Enrique's side were threatening to breeze to another trio of trophies this season. That incredible run, which started in October, looked to be leading them to a comfortable conclusion in La Liga, but they have started to show signs of tiredness at the worst possible stage.
Granted, Enrique's team did manage to come from behind against Atletico last week to ensure that they would take an advantage into the second leg, but they have lost their last two in the league and will enter this match off the back of a 1-0 defeat at Real Sociedad at the weekend, which has seen their lead at the summit cut to just three points.
The Spanish giants are still the favourites to claim La Liga and the Copa del Rey this season, but they have work to do in the Champions League as they prepare to tackle an Atletico team that can sense blood.
Barcelona have won this competition on four occasions in the last 10 seasons, however, and are attempting to become the first team since the great AC Milan in 1989 and 1990 to win back-to-back European Cups. They are in the quarter-finals for the ninth consecutive campaign, which is some record in itself, and have won 17 of their 22 fixtures in this competition since last season.
The Catalan outfit have also progressed in 38 of the 40 UEFA competition ties where they won the first leg at home, most recently against Bayern Munich in the semi-finals last season. What's more, of teams that managed a 2-1 success at home in the first leg of a Champions League knockout tie, 52% have gone on to progress in the next round, including the last four.
The 'MSN' trio Lionel Messi, Suarez and Neymar will enter the match with 109 club goals between them for the season, but Messi is currently on his worst Barcelona scoring run for five years, having gone 362 minutes without netting in any competition.
Another treble could well arrive for Barcelona this season, but there is no question that their performance levels have dipped in recent weeks. Atletico, away from home, is one of the toughest fixtures in the European game and Enrique's side will need to dig deep as they attempt to recover from what has been a difficult couple of weeks.
Recent form: WWDWWW
Recent form (all competitions): WWDLWL
Team News
Atletico boss Simeone is once again expected to be without the services of centre-backs Jose Gimenez and Stefan Savic, leaving young Frenchman Lucas Hernandez to partner Diego Godin at the heart of the defence.
Fernando Torres, meanwhile, is suspended following his red card in the first leg. Luciano Vietto could come in at centre-forward, but Simeone might well decide to select leading scorer Antoine Griezmann through the middle, with support from Saul Niguez and Yannick Ferreira Carrasco in the wide positions.
Augusto Fernandez should start alongside Gabi and Koke in a midfield three, leaving Thomas Partey and Matias Kranevitter as the midfield back-up on the bench.
As for Barcelona, Gerard Pique had been expected to miss out with a hip problem, but it is now understood that the Spanish international will play with a pain-killing injection.
Suarez will return from a league suspension to start alongside Neymar and Messi in the final third, while Andres Iniesta, Jordi Alba and Marc-Andre ter Stegen should also return to the XI.
Jeremy Mathieu and Rafinha, however, will miss out with knee and hamstring injuries respectively.
Atletico possible starting lineup:
Oblak; Juanfran, Godin, Lucas, Luis; Gabi, Koke, Augusto; Saul, Griezmann, Carrasco
Barcelona possible starting lineup:
Ter Stegen; Alves, Pique, Mascherano, Alba; Rakitic, Busquets, Iniesta; Neymar, Suarez, Messi
Head To Head
As mentioned, these two domestic rivals also met at the quarter-final stage of the 2013-14 Champions League and it was Atletico that advanced courtesy of a 2-1 aggregate win. That year, the first leg also took place at Camp Nou, where it finished 1-1, before Atletico recorded a 1-0 win in the return.
Atletico are actually the only team to prevent Barcelona from reaching the semi-finals of the Champions League in the last eight seasons and are one of just three clubs to have eliminated the Catalan outfit in the quarter-finals of this competition. That said, Barcelona have won their last seven games against Atletico in all competitions – including both La Liga fixtures this season.
Overall, Atletico have hosted Barcelona on 109 occasions in all competitions. They have won 50 of those matches, but have also been beaten on 36 occasions.
We say: Atletico 1-1 Barcelona (Barcelona 3-2 on aggregate)
It is a very, very tough game to call. Barcelona will enter the match off the back a couple of disappointing results, but they have had Atletico's number in their recent meetings and will back themselves to finish the job in the capital. Both teams will likely score in the second leg, but we can just see Barcelona grinding out a 1-1 draw and progressing into the semi-finals once again 3-2 on aggregate.