He has partnered January recruit Philipp Wollscheid for the last two-and-a-half games, and has been impressed by how the new boy has settled in to the Premier League.
"I've had a good run of games at centre-back and I always focus to play, to do well. I like to study the strikers," he told The Sentinel.
"Philipp is a really good guy, a strong guy who likes to play football like me. He's really good with the ball and he's a really good player."