Picture : Erling Haaland Power 5 !

Most prolific one-game scorers in European Cup/Champions League

In the game Manchester City vs RB Leipzig (7-0), Erling Haaland became the 3rd player to score 5 goals in a single Champions League match since 1992, after Lionel Messi in 2012 (also round of 16) and Luiz Adriano in 2014 (group stage).
Besides, there were two penta-tricks in qualification stage (Mihails Miholaps and David Lafata).
In the era of European Cup, since 1955 to 1992, there were another 10 pen-tricks.
Here in the table, we summarize all 15 such cases over the whole history of the biggest European club competition.
Haaland was so close to become the first ever author of 6 goals in a game, with 30 minutes yet to play after scoring five, and he wanted to score more.   
What a pity that Guardiola took him off the field so hastily and prevented a new record from being achieved!

 PlayerCountryGoalsClub DateGame
1Owe Ohlsson Sweden5IFK Göteborg 23/09/1959Linfield 6-1
2Bent Löfqvist Denmark5B191313/09/1961Spora Luxembourg 9-2
3José AltafiniBrazil, Italy5Milan12/09/1962Union Luxembourg 8-0
4Raymond Crawford England5Ipswich Town 25/09/1962Floriana 10-0
5Nikola Kotkov Bulgaria5Lokomotiv Sofia 10/09/1964Malmö 8-3
6Flórián Albert Hungary5Ferencváros08/09/1965Keflavík 9-1
7Paul Van Himst Belgium5Anderlecht14/09/1966Haka 10-1
8Gerd Müller Germany5Bayern Munich 24/10/1972Omonia Nicosia 9-0
9Claudio Sulser Switzerland5Grasshopper13/09/1978Valletta 8-0
10Søren Lerby Denmark5Ajax24/10/1979Omonia Nicosia 10-0
11Mihails Miholaps Latvia5Skonto21/07/1999Jeunesse Esch 8-0
12Lionel MessiArgentina5Barcelona07/03/2012Bayer Leverkusen 7-1
13David LafataCzech Republic5Sparta Prague15/07/2014Levadia Tallinn
14Luiz AdrianoBrazil5Shakhtar21/10/2014BATE Borisov 7-0
15Erling HaalandNorway5Manchester City14/03/2023RB Leipzig 7-0