BARCELONA: As if a combined 16 European Cups weren't enough, the Champions League quarterfinal between Real Madrid and Bayern Munich will also offer an intriguing duel between master and pupil.

Zinedine Zidane's transition from retired player to successful coach at Madrid owes a lot to his time at the club under current Bayern boss Carlo Ancelotti.

Come Wednesday, the former colleagues will face off in the first of two contests to determine which will guide his team to Europe's final four.

"We're ready for Real," said Ancelotti, who led Madrid to the 2014 title with Zidane as his assistant, a run which included defeating Bayern 5-0 on aggregate in the semifinals.

Two years later, it was Zidane's turn to lift the European Cup as Madrid's manager, just four months after taking the job over from Ancelotti's short-lived replacement, Rafa Benitez.

Toni Kroos, who left Bayern for Madrid when Ancelotti was still in charge, gives credit to Zidane for taking Madrid back to the top.

"He has had a huge impact here. He brought positivity when he arrived and took us in a new direction," Kroos said. "We are playing better football than before and that was rewarded when we won the Champions League last season."

The powerhouses' meeting will be their 23rd, a record for UEFA club competition.

"They will be two fantastic games. This tie could easily be the Champions League final," Kroos said.

Here is a look at all four quarterfinals:

JUVENTUS vs BARCELONA

Barcelona returns to the Champions League on Tuesday for its first match since its historic 6-1 victory over Paris Saint-Germain that made it the first team to overturn a 4-0 first-leg loss in the history of the competition.

But the Catalan club heads into the rematch of the 2015 final it won against Juventus on the heels of a 2-0 loss at Malaga on Saturday. The defeat included a red card for Neymar and damaged its chances of retaining the Spanish league title.

"That shouldn't be considered, it doesn't change anything," Juventus coach Massimiliano Allegri said. "Barcelona is a team which is used to playing big matches like this."

Allegri could welcome striker Mario Mandzukic back from injury, while Barcelona midfielder Sergio Busquets is suspended.

BORUSSIA DORTMUND vs MONACO

It may lack the big names and champion pedigree, but if you want goals then look no further than Tuesday's match between Borussia Dortmund and Monaco.

Monaco has scored a whopping tally of 133 goals in all competitions this season, including a bundle by teenage standout Kylian Mbappe.

The 18-year-old forward, newly capped by France, has netted 12 times in his last 11 games and 19 for the season. He scored in both legs against Manchester City in the Round-of-16.

Dortmund is no slouch either, led by Pierre-Emerick Aubameyang's 32 goals overall.

But Dortmund is facing serious injury worries. It was without Marco Reus, Andre Schuerrle, Sven Bender, Julian Weigl, Shinji Kagawa, Erik Durm and Lukasz Piszczek in a 4-1 loss to Bayern on Saturday.

ATLETICO MADRID vs LEICESTER

As the only side in the quarterfinals that had to play a domestic fixture as late as Sunday, Leicester comes into the match having lost its unbeaten record under new manager Craig Shakespeare after falling 4-2 at Everton.

The Premier League champions had won six consecutive games, including its Round-of-16 victory over Sevilla, after sacking Claudio Ranieri.

However, with Shakespeare making five changes to his starting lineup, Leicester should be at full strength in Madrid.

"We're all excited for Wednesday night and it's going to be a great occasion, but we have to improve on that performance today," winger Marc Albrighton said.

Atletico is playing its best football of the season and got a big boost Saturday from Antoine Griezmann, whose late equalizer earned a 1-1 draw at Real Madrid.

BAYERN MUNICH vs REAL MADRID

Besides relying on its own potent attack, Bayern will also hope that Cristiano Ronaldo continues to struggle in front of goal this season in Europe.

The Champions League's all-time scorer with 95 career goals has only struck twice this campaign. That has allowed Barcelona rival Lionel Messi to close the gap after scoring 11 goals to take his total to 94.

Bayern arrives in fine form, enjoying a 10-point lead in the Bundesliga.

The German side will be without defender Mats Hummels (ankle), while Madrid will likely be missing defenders Pepe (ribs) and Raphael Varane (leg).