This is Xhaka’s second spell in England, having played 297 times for Arsenal from 2016 until 2023.
He then joined Bayer Leverkusen where he won the title under Xabi Alonso in their unbeaten domestic season in 2023-24.
Erik ten Hag, then the Leverkusen boss, insisted Xhaka would not be sold this summer.
But the midfielder left for Sunderland, and Ten Hag was sacked a few weeks into the season.
“I didn’t expect to come back after Germany but you never know where you land,” said Xhaka.
“To be back made me happy. I knew the project to bring experience and show the guys day by day.
“It makes me happy to score a goal.”
Xhaka was a bit of a pantomine villain – and sometimes much maligned – at Arsenal.
He was sent off five times for the Gunners and spent six weeks as captain in 2019, clashed with his own fans and was stripped of the armband.
But things went better under Mikel Arteta and he became an important player before leaving in 2023 for Germany.
Carragher said: “After what he went through at Arsenal, he showed great character to come back from that. The impact he has had, if he can be part of a Sunderland team who finishes in the top 10 – or even just stays up – he will be remembered for a very long time.”
Former Sunderland striker Marco Gabbiadini told BBC Radio Newcastle: “He exemplifies a top professional.
“When he was an Arsenal player at times you felt like he was a bit of a villain. Over the years we have seen him mature and develop.
“We’ve seen a slightly more restrained version of Xhaka, but it’s actually better than the fully committed, blowing steam out of his ears sort of player that we saw at Arsenal.
“He’s a little bit more measured, calmer and a better professional. To have that in your squad especially when you’ve got a young squad, and everyone believes in him, he’s a talisman.
“We need to wrap him in cotton wool and keep him going for 38 games.”