PSG defeated Real on Match day 1 and will clinch first place in Group A if they avoid defeat at the Santiago Bernabeu. It's not the same for a manager after five years as two - everyone is fresh after two.
Bigger tests will come for Mourinho and Spurs, in both competitions, but they couldn't ask for much more than a pair of wins and qualification for the Champions League knockouts in his first week in charge.
Bayern earned their fifth straight win in Europe, having already qualified for the last 16 in the previous round of matches.
Dele Alli pounced on a frightful defensive mistake to breathe new life into Spurs before the break and a second half double from Harry Kane either side of Serge Aurier's fine strike completed the comeback.
Real Madrid qualified for the last 16 of the Champions League before taking to the field on Tuesday after Group A rivals Club Brugge drew 1-1 with Galatasaray in Istanbul.
But confusion between defender Raphael Varane and Madrid keeper Thibaut Courtois allowed Kylian Mbappe to bring PSG back into the contest with a goal in the 81st minute. Gareth Bale hit the post with a free kick in injury time for Madrid.
Galatasaray a first victory in group A were refused as Club Brugge scored a stopping time-time equalizer and then let two men leave in a 1-1 draw.
The biggest victor Tuesday was Bayern, whose striker Robert Lewandowski scored four goals in 15 minutes in a 6-0 win at Red Star Belgrade.
A whole host of clubs can book their place in the next round, while some can even be crowned as winners of their group. Oh, and don't forget Ronaldo and Juventus going up against Atletico.
Dybala ensured Juventus will finish top of Group D by scoring a free kick on the stroke of halftime from a near-impossible angle, about two meters in from the byline.
Atleti, with 7 points, are just 1 ahead of Bayer Leverkusen, 2-0 winners Tuesday over Lokomotiv Moscow.
Guardiola's City broke numerous records as they clocked up 100 points in winning the Premier League in 2018 and followed up by claiming a domestic treble last season.
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The draw for the last 16 of the Champions League will take place on Monday December 16 in Nyon, with a procedure starting at 11 AM (UK). Tottenham marked Mourinho's first home match in charge by coming from two goals down to beat Olympiakos 4-2 and reach the Champions League's knockout stage with a game to spare. Sven Bender added the second with a brilliant volley.
In the other early kick-off on Tuesday, Bayer Leverkusen kept alive their chances of reaching the last 16 thanks to a 2-0 win away to Lokomotiv Moscow in Russian Federation.
The Italians are still in contention to qualify after beating Dinamo Zagreb 2-0 thanks to Luis Muriel's penalty and a cracking Alejandro "Papu" Gomez goal.
Shakhtar Donetsk are second in Group C with six points and are favorites to qualify.