Having set a new Champions League record last time out, Erling Haaland is fast approaching another.
The Manchester City striker became the fastest player to score 50 goals in the competition with one against Napoli last month. His half-century came in his 49th appearance -- smashing Ruud van Nistelrooy's record of 50 in 62 games.
Now Lionel Messi's record is in his sights and also looks certain to fall.
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Messi is the fastest player to reach 60 goals in European club soccer's top competition. He managed it in 80 appearances. Haaland's double against Monaco on Wednesday means he is on 52 after just 50 games.
But the Norway international could not hide his frustration as City squandered victory by conceding a late penalty for a 2-2 draw.
"It isn't good enough," Haaland said. "We have to try to win the next game. It is the only thing we can do."
Haaland's goals twice gave City the lead at Stade Louis II.
He fired the visitors ahead in the 15th minute only for Jordan Teze to level the game three minutes later.
Haaland struck again in the 44th, but when Nico González was penalized for a high boot following a VAR intervention, Eric Dier converted from the spot.
Asked if he would give his opinion of the penalty incident, Guardiola said: "No. I have nothing to say to the Spanish referees."
There were ugly scenes as the referee was trying to watch the replay. City goalkeeper Gianluigi Donnarumma raced to the bench to speak to his coaches ahead of the anticipated spot-kick, but took the ball with him and Monaco's players ran after him.
In the resulting melee at least one Monaco coach was sent off, with City captain Bernardo Silva booked on his return to his former club.
But Guardiola's bigger frustration will have been his side's inability to kill off Monaco.
"In football you have to win with the result," he said. "If you analyse the game there were many things that were really good. Step by step we will be better but we had many chances. Phil [Foden] in the first half and many players played really good.
"We conceded almost nothing. We created chances, they defended so deep and tight, that it wasn't expecting for the way they play but we adjusted and we played really good. When it's close, you have to defend and we take the point."
Haaland's latest goals extended his outstanding scoring run at the start of the season.
He is now on 17 goals in 10 games for club and country. City's 2-0 loss to Tottenham in August in the only game he hasn't managed to score in this term.
Information from The Associated Press and PA was used in this report.