The Champions League returns on Tuesday evening, with Manchester City among the teams in action.
The Spaniard is arguably the greatest manager ever and he'll be looking to win his third Champions League title.
But how does his playing career match up with the other 31 managers in the Champions League group stage?
And we've decided to do it again for the 2020/21 season. We've ranked every Champions League group stage manager by their playing careers from worst to best below.
=31. Murad Musayev | Krasnador
Musayev did not play professional football.
=31. André Villas-Boas | Marseille
Villas-Boas did not play professional football.
30. Marko Nikolić | Lokomotiv Moscow
Nikolic spent time in the Serbian third tier on loan at Dorćol before retiring through injury.
29. Julian Nagelsmann | Leipzig
Nagelsmann played youth football at FC Augsburg and 1860 Munich but persistent knee injuries forced him to retire before he made a professional appearance.
28. Julien Stéphan | Rennes
Little is known about Stephan's playing career, but he did spend time at Toulouse, RC Paris, Stade Briochin and Drouais.
27. Thomas Tuchel | Paris Saint-Germain
Tuchel's best spell as a professional footballer came at German third-tier side, SSV Ulm.
He was a mainstay for Ulm for four years but was forced to retire at the age of 25 after suffering a chronic knee injury.
26. Luís Castro | Shakhtar
Castro spent much of his career in Portugal's lower leagues, but did play for Vitória S.C. and Elvas in the Primeira Liga.
With the latter, Castro played 28 times in the 1987/88 season as his side were relegated from Portugal's top tier.
25. Jesse Marsch | Salzburg
Marsch spent his entire career in the MLS, featuring for D.C. United, Chicago Fire and Chivas USA.
He made 331 appearances across 13 years, scoring 31 times.
Marsch won the MLS Cup on three occasions and made two appearances for the United States.
24. Marco Rose | Gladbach
Rose played for Leipzig and Hannover before joining Jurgen Klopp at Mainz 05 in 2002.
He helped them reach promotion to the Bundesliga in his first year at the club. He made 150 appearances in the league across across an eight-year spell.
23. Jurgen Klopp | Liverpool
Klopp confesses he wasn't very good at all, but we think he's been a little harsh on himself.
He spent the large majority of his playing days in the German second tier with Mainz 05, where he played for 11 years.
He retired as their record goal scorer, notching 56 times in total.
22. Gian Piero Gasperini | Atalanta
Gasperini started his career at Juventus but he never made the grade.
He spent the early parts of his career in Italy's lower leagues, playing five seasons for Palermo in Serie B from 1978-1983.
The Italian midfielder finally got the chance to play in the Serie A with Pescara after helping them win promotion in 1987.
He made 469 appearances in his career, scoring just once.
21. Erik ten Hag | Ajax
Ten Hag made 336 appearances during his playing career, most of which came for Twente.
He helped them to a KNVB Cup triumph in 2001.
20. Lucien Favre | Dortmund
Favre spent much of his career in Switzerland playing with Servette, although he did spend a solitary season with Toulouse.
He played 24 times for Switzerland, scoring once.
19. Mircea Lucescu | Dynamo Kiev
Lucescu had a good career in Romania with Dinamo București.
He was capped 70 times by his country and helped his club side win six league titles.
18. Brian Priske | FC Midtjylland
Priske, a defender, spent a season at Portsmouth in the Premier League during the noughties.
He also played for Club Brugge, Genk and AaB. He earned 24 caps for Denmark.
17. Pedro Martins | Olympiacos
Martins started his career at Feirense, before moving on to Vitória S.C. and then Sporting Lisbon.
The fact he made one appearance for Portugal means he must have been a decent player.
16. Julen Lopetegui | Sevilla
Lopetegui, a goalkeeper, is one of a few players that can claim to have played for both Real Madrid and Barcelona.
He wasn't successful at either club, though. The Spaniard spent most of his career in La Liga with Rayo.
He managed one appearance for Spain, coming in 1994.
15. Philippe Clement | Club Brugge
After impressing in a three-season stint with Genk, Clement moved to Premier League outfit Coventry in 1998.
The defender failed in England but then went on to become a legend at Club Brugge as he made 256 appearances across 10 seasons.
Clement played 38 times for Belgium, scoring once.
14. Hans-Dieter Flick | Bayern Munich
Flick made 104 appearances for Bayern from 1985-1990, helping the German side win four Bundesliga titles.
He moved to Koln before retiring from professional football through injuries at the age of 28.
13. Sergei Semak | Zenit
Semak made a name for himself at CSKA Moscow, where he scored 69 times in 289 games.
He went on to play for Paris Saint-Germain before ending his career with Zenit.
Semak played 65 times for Russia, scoring on four occasions.
12. Okan Buruk | Istanbul Başakşehir
Buruk won seven league titles with Galatasary in what was a successful playing career.
He made 56 appearances for Turkey and also spent time at Inter Milan and Besiktas.
11. Simone Inzaghi | Lazio
Simone wasn't as good as his brother, Filippo, but he still enjoyed a decent career.
He spent the majority of his career at Lazio, scoring 54 goals in 179 games.
10. Serhiy Rebrov | Ferencváros
Rebrov had a very good career, having spent time at Tottenham, West Ham and Dynamo Kyiv.
He scored 15 times in 75 games for Ukraine.
9. Sérgio Conceição | Porto
Despite a successful career, Conceição was a bit of a journeyman, featuring for 10 different clubs.
He won six trophies with Lazio, including Serie A, as well as three Primeira Liga titles. He also made 56 appearances for Portugal, scoring 12 times.
8. Antonio Conte | Inter Milan
Conte signed for Juventus from Leece for €3.60m in 1996 and he would justify that price tag in a highly successful spell.
He helped Juventus to 13 major honours, including five Serie A titles and a Champions League victory in 1996.
He made 20 appearances for Italy.
7. Diego Simeone | Atletico Madrid
Simeone made his name in Spain with Sevilla before moving to Atletico Madrid in 1994.
He helped the club to a domestic double in 1996 as they lifted the Copa del Rey and La Liga.
He would then have success with Inter, before winning the treble with Lazio in 2000.
The defensive midfielder also made his mark on the international stage, appearing 106 times for his country and winning two Copa America's.
6. Ole Gunnar Solskjaer | Man United
Solskjaer is one of the best finishers that the Premier League has ever seen. He spent 11 years at Man United, helping them win 12 trophies.
Known for his ability to score after coming off the bench, the Norwegian scored 126 times in 366 games for United.
Unfortunately, knee injuries curtailed his career and stopped him from achieving even more.
5. Pep Guardiola | Man City
Guardiola was a very classy player. He spent 11 years at Barcelona, where he won six La Liga titles and a European Cup.
He also made 47 appearances for Spain and was named in the Euro 2000 Team of the Tournament.
4. Ronald Koeman | Barcelona
Koeman scored a ridiculous 253 goals during his career, despite being a defensive minded player.
He enjoyed great success in Holland with Ajax and PSV and Spain with Barcelona.
He won two European Cups - one each with PSV and Barcelona - as well as eight league titles across his career.
The Dutchman was also named in the Team of the Tournament as he helped his country win Euro 1988.
3. Andrea Pirlo | Juventus
Pirlo could do things with a football that people can only dream of. He was the definition of cool: he possessed incredible technical ability and it was almost impossible to get the ball off him.
He was extremely successful during his time at AC Milan and Juventus. He won six Serie A titles in his career and two Champions League's.
The elegant midfielder also won the World Cup with Italy in 2006.
2. Frank Lampard | Chelsea
Lampard is one of the best goal scoring midfielders ever.
After impressing in a six-season stint with West Ham, Lampard made the move to Chelsea in 2001.
He would become arguably their greatest ever player across a 13-season spell, scoring a ridiculous 211 goals in 648 games.
The Englishman won three Premier League titles and a Champions League with the Blues.
1. Real Madrid | Zinedine Zidane
Pirlo, Koeman and Lampard were all brilliant. But Zidane was in a league of his own.
Zidane is a legend at Juventus, Real Madrid and for France, where he made 108 appearances and helped them to the Euro 2000 title.
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