Real Madrid was tied 1-1 by Riyadh Crescent in the Club World Cup, and Arnold completed his debut, which was ruthlessly ridiculed by Liverpool fans.
A Liverpool fan wrote on Twitter: "He thought he had a chance to win the Golden Ball."
Another fan quoted Arnold's comments praising Real Madrid's training level and said: "The balls move so fast here."
A fan left a message under the video of Arnold's intercepted ball in the frontcourt: "Here he is (helping his opponent) to counterattack his team."
Walker was also innocently caught in the gun because another fan wrote: "Bro is worse than Walker."
A fan said: "Wow, he is really bad. It's a scam to ask Real Madrid to pay 10 million pounds."