At a glance
Bukayo Saka opens the scoring from the penalty spot
Mikel Merino adds two more in second half
Max Dowman becomes youngest ever player in Champions League
Slavia Prague have late penalty overturned by VAR as Arsenal extend clean sheet run to eight matches
Mikel Merino scored twice as Arsenal comfortably beat Slavia Prague in the league phase of the Champions League to extend their winning run to 10 matches in all competitions.
It was also an eighth successive clean sheet - matching a club record set back in 1903 over two different seasons.
Spaniard Merino was starting up front in place of the injured Viktor Gyokeres and, just as he did last season when he deputised for Kai Havertz, the midfielder showed his versatility to provide a focal point and make a crucial contribution for his team.
Arsenal's opening goal came in the 32nd minute when they were awarded a penalty after the video assistant referee (VAR) penalised Lukas Provod for handball after Gabriel flicked on a corner.
Captain Bukayo Saka stepped up to drill the ball into the bottom corner.
The Gunners weren't at their best in the first half and had to navigate a tricky opening period, with Provod shooting wide for Slavia Prague when well placed.
But Mikel Arteta's side started the second half extremely well and doubled their lead seconds after the restart when Merino volleyed Leandro Trossard's cross into the bottom corner.
He added his second in the 68th minute when he rose to meet a Declan Rice cross as home keeper Jakub Markovic came out but failed to collect the ball.
There was also another piece of history on the night as Max Dowman, at 15 years and 308 days old became the youngest player to feature in the Champions League when he replaced Trossard - breaking the mark set by Youssoufa Moukoko at 16 years and 18 days with Borussia Dortmund in 2020.
Slavia Prague thought they had a penalty late on when Provod went down after a high challenge from Ben White, but the decision was overturned by a VAR check once the referee was sent to the monitor.
The victory continued Premier League leaders Arsenal's excellent start to the season, with four wins from four matches in the Champions League as they extended their unbeaten run to 13 matches in all competitions.
No Gyokeres, no problem - makeshift Merino provides Arsenal 'solution'
- Published4 November
Arsenal's Dowman youngest Champions League player at 15
- Published4 November
Arsenal's Gyokeres may have injured hamstring
- Published4 November
Analysis: Merino steps up again to show value
Merino's versatility is a 'joy' for Arsenal - Arteta
With concern about the muscular injury that had left Gyokeres sidelined, Arsenal needed someone to step up to lead their attack - and it was Merino again who reminded supporters of his value.
The 29-year-old has dropped out of Arsenal's starting XI in the Premier League, but has still managed to deliver big moments for his team.
He scored the crucial equaliser to spark a vital comeback success at Newcastle - the last time the Gunners conceded a goal too.
This time Merino sealed a confident and comfortable victory in Prague as a makeshift forward.
When asked to play that role last season in the absence of Havertz and Gabriel Jesus, he shone too, taking his season's tally to nine.
Vital goals came in wins over Real Madrid, Chelsea, Fulham and Leicester, and his double against Slavia Prague showed why Arteta appreciates him.
Merino is a very different type of forward to Gyokeres, who looks to run behind the defence whenever he can, while the Spaniard provides a good presence for the Arsenal attack and snaps up chances.
He is also part of the club's leadership group and the Gunners have never lost a game in which Merino has scored.
What's next for these teams?
Arsenal are next in action on Saturday, 8 November (17:30 GMT) when they visit Sunderland in the Premier League. Their next game in the Champions League will be at home to Bayern Munich on Wednesday, 26 November (20:00 GMT) before visiting Club Brugge on Wednesday, 10 December (20:00 GMT).
Slavia Prague host Athletic Club on Tuesday, 25 November ( (20:00 GMT), before they visit Tottenham in their next tie on Tuesday, 9 December (20:00 GMT).
Player of the match
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