Manchester United manager Ruben Amorim hailed Arsenal as one of the best set-piece teams he has ever faced following the 2-0 defeat at Arsenal.The Gunners took two points out of Liverpool’s lead at the summit of the Premier League after Jurrien Timber and William Saliba struck in the second half – both from corners – to condemn Amorim to his first defeat as United boss.The hosts’ second-half strikes took their goals-from-corners tally to 22 since the start of last season – a statistic that is unmatched by any other team in the division.Asked if Arsenal are one of the best teams he has come up against on corners, Amorim replied: “If you follow the Premier League for a long time you can see that.“They are also big players and you see every occasion when (Gabriel) Martinelli and (Bukayo) Saka have one-on-ones, a lot of times they go outside and they cross, and they know that if the cross goes well, they can score, and if it is a corner they can score, too, so we have to be better on that.“You have seen in all Arsenal games that every team have had problems with that (corners). And the difference today was the set-pieces.