Brian Brobbey struck on 90 minutes as Sunderland won 2-1 at St James' Park.
Xhaka said afterwards: "If you want to play these games you need personality. It's not easy to play here. We knew before the game what it means to come here to take something or to win. If you see all the game, three points are deserved.
"We didn't find solutions in the beginning. It's part of the game, a part of our journey. We spoke at half-time about things, we changed and second half was nearly perfect."
On what the win says about Sunderland:, Xhaka insisted: "We need to step up. Some players didn't have a lot of minutes.
"We are a team, it's not just the first 11. Today was a great win for all the team. After three defeats in a row, today was a very important three points. Now we go to the national team and come back for the last run."