Arsenal manager Mikel Arteta selected the Ivorian after he apologised to the squad for his actions against Leeds and he repaid his faith by scoring the opening goal during the 3-0 win in Norway.
Reiss Nelson and Folarin Balogun wrapped up the victory for Arsenal, which means they qualify for the knockout stages of the Europa League as winners of Group B, but it was Pepe who stole the show.
The winger emphatically bounced back from his red card at Leeds and Mustafi believes the way the whole squad supported Pepe shows the culture needed to win trophies.
“Nico is part of the team,” said Mustafi.
“We all make mistakes and we all go through periods where things aren’t going the way you want them to go, but I think the most important thing is that the team stays behind everyone and in my opinion this is our strength.
“If you want to win something or achieve something, those are the little details that can make the difference.
“I think the team responded really well and I think it was important that Nico lifted his hand and said sorry to everyone, and he’s still young as well.
“Everyone accepted it and I think coming here today and scoring a goal, he helped the team and I think going forward today he asked a lot of questions.
“This is the response that we all wanted from him and I hope that we can keep supporting him and giving him the confidence that he needs to score those goals.”
While Thursday was a big night for Pepe, who will miss Sunday’s Premier League game with Wolves due to suspension, it was a memorable one for Balogun, too.
The 19-year-old came off the bench to score his first senior goal for Arsenal, finding the net with almost his first touch.
Balogun’s contract is due to expire at the end of the season, but Arteta wants him to stay and Mustafi too has been impressed by the youngster’s rise.
“He’s a very strong and intelligent player. He’s a good striker and he’s hungry,” he said.
“I think at this age in strikers you can always see that hunger to score and they always want to do something in the box, and I think for him it was really nice.
“He came on in the last game as well and this time it was his first touch he scored with, so I’m very happy for him because I think this is something that is very important.
“We all started as young boys and everyone knows the feeling of how difficult it is to come to the first team and perform the way you perform with the youth team, so we have to give him credit and hope it’s a sign of more coming in the future.”
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