Sunderland have completed the signing of Sotirios Kyrgiakos on a six-month loan deal from Wolfsburg.
The Greek international will begin his second stint in the Premier League, having represented Liverpool for two seasons.
"Sotirios offers a real physical presence, coupled with a wealth of experience, which will be an undoubted benefit to us in the next few months," Sunderland manager Martin O'Neill told the club's official website.
"I'm delighted to welcome him to the club and I'm sure he is looking forward to the challenge of returning to the Premier League."
Kyrgiakos, 32, made 49 appearances for Liverpool.