Wednesday's Champions League action is headlined by the second leg of Atletico Madrid's last-16 tie against cross-city rivals Real Madrid, which remains firmly in the balance.

Rodrygo and Julian Alvarez traded spectacular first-half finishes last week at the Santiago Bernabeu, before Brahim Diaz's fine individual effort gave Madrid a 2-1 lead to protect.

Los Blancos have not made a habit of giving up first-leg leads in Europe's premier club competition over the years.

Indeed, they have progressed from 21 of their last 22 Champions League knockout ties when winning the first leg, the exception being against Ajax at this stage in 2018-19.

Under Carlo Ancelotti, Madrid have progressed from all nine of their Champions League ties when protecting a first-leg advantage.

But Atleti have been a thorn in the side of their more illustrious neighbours for some time now. 

They were the only team to beat Los Blancos in LaLiga last season and also dumped them out of the Copa del Rey, while they have earned two 1-1 draws against their rivals in league action this term.

Diego Simeone will certainly not allow his side to roll over, and he said Kylian Mbappe's failure to find Vinicius Junior for a late tap-in in the first leg may have "opened the door" for an Atleti fightback.

There is no love lost between these two neighbours, and fireworks are anticipated at the Metropolitano Stadium.

What's expected?

The Opta supercomputer makes Real Madrid favourites to progress to a likely quarter-final tie with Arsenal.

Los Blancos are assigned a 34.6% chance of winning the second leg inside 90 minutes, with 39.6% of simulations going Atletico's way and 25.8% being drawn.

Overall, Ancelotti's team reach the last eight in 72.4% of projections, while Atleti do so in 27.6%. 

Real Madrid have won or advanced from all five of the teams' previous ties in the knockout stages of the European Cup/Champions League, including final victories in 2014 and 2016. They also won two-legged ties between the teams in 1958-59, 2014-15 and 2016-17.

But Atleti have a solid record against their rivals lately, particularly on home soil, only losing one of their last seven home matches against Madrid (three wins, three draws).

Simeone's men are also unbeaten in the last five derbies in cup competitions on their own ground, winning four and drawing one; a 4-2 extra-time victory in the Copa del Rey last January.

Will fortress Metropolitano stand firm?

Asked about the impact of Atleti hosting the second leg, Simeone said: "It is always a stimulus, our people push us and give us energy."

There are few places more difficult to go to as a visiting team than the Metropolitano, where Los Colchoneros have an incredible record in Europe.

Atletico Madrid have not lost a Champions League knockout game at one of their home stadiums – either the Metropolitano or their former home at the Vicente Calderon – since March 1997.

Atleti are unbeaten in 18 such matches (11 wins, seven draws) since that 3-2 quarter-final defeat to Ajax, a game in which Simeone started for them in midfield.

Since losing 3-1 to Lille in the group phase of this competition in October, they are unbeaten in 12 home games across all competitions, winning 10 and drawing two, while they have only conceded three times in their last eight.

Real Madrid, meanwhile, have only won on three of their last 17 trips to Atletico (seven draws, seven losses), since winning eight away derbies in a row between 2008 and 2014.

The ferocious backing of their home fans will no doubt give Atletico a boost, and they also have a series of memorable European comebacks to look back on for inspiration.

Atletico have lost the first leg in six previous Champions League knockout ties and have recovered to progress from three of those, with all three instances coming when at home in the second leg under Simeone.

They beat Bayer Leverkusen in a penalty shoot-out in the last 16 in 2014-15, overcame Barcelona 3-2 on aggregate in the 2015-16 quarter-finals, and eliminated Inter on spot-kicks at this stage last season.

Don Carlo hopes to celebrate landmark

The most successful coach in Champions League history will bring up another landmark on Wednesday, and he will hope to celebrate it with safe passage to the last eight.

This will be Ancelotti's 75th Champions League game in charge of Madrid, a figure no other coach has reached with Los Blancos in European Cup/Champions League history.

The Italian's 74 games are already three more than the legendary Miguel Munoz managed in two spells at the helm between 1959 and 1974.

Ancelotti – who has also overseen 73 games in the competition with AC Milan, 18 with Chelsea, 12 each with Bayern Munich and Napoli, and 10 with both Juventus and Paris Saint-Germain – will be just the eighth coach to bring up 75 games with a single team.

Alex Ferguson (190 with Manchester United), Arsene Wenger (177 with Arsenal), Simeone (114 with Atletico), Pep Guardiola (95 with Manchester City), Valeriy Lobanovskyi (80 with Dynamo Kyiv), Marcello Lippi (76 with Juventus) and Ottmar Hitzfeld (76 with Bayern) have previously done so.

Rarely have Ancelotti's side looked quite so free-flowing in Europe, averaging 2.55 goals per game in the Champions League this season. Only in one campaign under the Italian (3.15 during his first spell in 2013-14) have they averaged more, and it is their best figure overall in the competition since 2016-17 (2.77).

While Vinicius and Mbappe have led the way for Los Blancos with seven goals apiece in the competition this campaign, Rodrygo has also chipped in with five. 

His first-leg opener was his 25th Champions League strike for Madrid, making him the fourth-youngest player (aged 24 years, 54 days) to score 25 for a single team in the competition, behind Lionel Messi for Barcelona (22 years, 286 days), Mbappe for PSG (22 years, 352 days) and Raul for Madrid (23 years, 252 days).

PLAYERS TO WATCH

Atletico Madrid – Julian Alvarez 

Alvarez scored with a wonderful strike from near the left corner of the box in the first leg, continuing his fine run of form in the Champions League.

The Argentine has been involved in at least one goal on each of his last five European appearances for Atletico, scoring six goals and assisting one during that span.

The only two Argentinian players to score or assist in six in a row in the Champions League are Claudio Lopez (six straight in 1999 for Valencia) and Messi (eight in 2011-12 and six in 2014 for Barcelona). 

Real Madrid – Luka Modric

In what is likely to be a red-hot atmosphere at the Metropolitano, control will be key for the 15-time European champions, meaning the metronomic Modric could play a part.

The Croatian could also make a difference going forward; he is averaging 17.7 line-breaking passes per 90 minutes in the Champions League this season, the most of any player to play at least 300 minutes. 

Only two Real Madrid players made more such passes than Modric (eight) in the first leg, despite him only coming off the bench in the 62nd minute.