Gareth Southgate has hit out at the section of fans who booed when England’s players took the knee before their friendly win against Austria at the Riverside Stadium on Wedesday night. Southgate cut an angry figure after the anti-racism gesture was greeted by loud boos just before kick-off. On a night when the right-back Trent Alexander-Arnold sustained a thigh injury during the closing stages – Southgate said he will be assessed in the next two days – the manager defended his players and stressed the act of taking a knee should not be seen as a political message. “I did hear it,” Southgate said. “It’s not something on behalf of our black players I wanted to hear because it feels as though it’s a criticism of them. I think we have got a situation where some people seem to think it’s a political stand that they don’t agree with. That’s not the reason the players are doing it. We’re supporting each other. I was pleased that was drowned out by the majority of the crowd. “We can’t deny the fact that it happened. I think the most important thing for our players to know is all their teammates and all the staff are very supportive. I think the majority of people understand it. I think some people aren’t quite understanding the message. I suppose we’re seeing that across a number of football grounds at the moment.” Bukayo Saka, who earned England victory with his first goal at international level, was similarly perplexed. “I don’t understand why they did it,” the 19-year-old said. “I heard some boos and I heard some claps. But you’ll have to ask the fans that were booing to understand why they did it.” England, who were without a host of key players against Austria, must wait to learn of Alexander-Arnold’s fitness. The Liverpool defender, who is one of four right-backs in Southgate’s squad, pulled up as full-time approached and was close to tears as he walked around the pitch. England, who host Romania in another warm-up game on Sunday, have six players on their stand-by list. Jesse Lingard, Ollie Watkins, Ben White, James Ward-Prowse and Ben Godfrey are the outfield players who could benefit from Alexander-Arnold pulling out. “We’ll have to assess him over the next 24 to 48 hours,” Southgate said. “The medical team are still assessing it. We just have to see. It’s not a good sign to see him have to walk off as he did. Let’s see how Trent is first and then we’ll go there. We don’t know the full extent. Clearly it’s not a good sign he looked in some discomfort.” Alexander-Arnold’s injury is another complication for Southgate, who is already likely to be without Jordan Henderson and Harry Maguire when England play Croatia in their opening group game. Henderson, who has not played since February because of a groin injury, was unavailable against Austria after feeling discomfort yesterday morning. “With Jordan we had hoped to involve him today,” Southgate said. “This morning he wasn’t so happy with how he felt. We’ve scanned him just to be certain. There’s no problem on the scan so he’ll be able to resume training but we’ve taken the decision to leave him out of the game.” Jack Grealish, who has just returned from injury, needed ice on his shin after being substituted. “I’ve had an injury recently so to get 70 minutes under my belt was a perfect week,” the playmaker said. “It’s not shin splints, it’s a bit of stress on my shin. I’m not concerned. I still need to keep on top of it, to heal it after the games, so that’s why I put the ice on it.”