Liverpool manager Jurgen Klopp celebrated his side’s individual defending as being as good as a goal after they ground out a 1-0 win at home to West Ham.
Sadio Mane scored the 27th-minute winner but right-back Alexander-Arnold was the architect of a victory which reduced Manchester City’s gap at the top of the Premier League to three points.
The England defender provided a career-best 16th assist but also produced a brilliant goalline clearance to deny Pablo Fornals.
And he was not alone in contributing to a clean sheet, with fellow full-back Andy Robertson and midfielder Naby Keita also delivering goal-preventing tackles.
“All these situations were like scoring a goal,” said Klopp after a 12th successive victory in a game in which Virgil van Dijk set a record of remaining 60 league matches unbeaten at home.
“It would not be a tactic. The organisation was wrong.
“I think because of the situation West Ham had we felt in a bit of a rush and needed to finish the game off. We needed to be calm, and we couldn’t finish it off.
“When you are not perfectly organised, or you don’t win the decisive challenge you have to use your legs, passion, big heart to defend.
“Robbo, Naby, then Ali (Alisson Becker) – we knew we needed some luck in these moments and some proper defending in a way, but I think it is difficult to deny them (chances) over 95 minutes.
“When you win 12 in a row then you can’t only win the ones when you are flying, and today we were not flying, we had to dig deep and that’s what the boys did.
“It’s necessary to get something out of this season, and so we keep on going. No time to rest.”
West Ham’s former Everton boss David Moyes left Anfield without a win for the 18th time, a Premier League record for one manager at a single ground.
The Hammers, already missing England midfielder Declan Rice through illness, suffered a blow when Jarrod Bowen – making a club-record 78th successive Premier League appearance – had to be helped off late in the second half.
Moyes said: “Jarrod looks like something in his heel. It happened in the tackle with Robertson.
“I was hoping that it wasn’t too bad but what I didn’t like was he came off with no weight bearing. We will get him scanned.
“It is not an obvious-looking injury, it looks like he has been caught near the Achilles or the heel.”
On the performance, which made it just two wins in the last seven league matches to halt their progress towards the top four, Moyes added: “I thought we played better than we had done, the performance levels were much better.
“We found it difficult in the opening 15-20 minutes, but I thought we grew into the game, we had shots on goal, we got behind Liverpool, we had one or two huge opportunities.
“We were just lacking that little bit of edge. Against the top teams we need to be more clinical.”