Real Madrid beat RB Leipzig 4-1 at the Santiago Bernabeu on Wednesday, their third win from three games in the Champions League league phase.
Madrid led 2-0 when Mbappe struck into the top corner in the 83rd minute to make it 3-0.
Leipzig pulled one back two minutes later, when Gomis took advantage of a defensive lapse.
Diomande, playing against his former club, scored in the 87th minute to restore the two-goal gap and seal a 4-1 win.
Madrid now have nine points, level with Paris Saint-Germain and Liverpool, and are in the race for automatic qualification to the round of 16.
In Munich, Bayern and Arsenal drew 2-2. Harry Kane's penalty put Bayern ahead before Declan Rice equalised in the 82nd minute.
The draw ended Arsenal's 14-match winning run in the league phase. Bukayo Saka went off with a leg injury after ten minutes.
Elsewhere, Como beat Manchester United 4-1, Galatasaray won 4-2 at Lille and Inter beat Shakhtar Donetsk 1-0 for their first win.
Read the full article for more on Real Madrid's win over Leipzig.
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