Joel Matip has been a revelation since joining Liverpool on a free in the summer transfer window.
Fast, strong and commanding in the air, the 25-year-old has thoroughly impressed and formed a solid defensive partnership with Dejan Lovren at the back.
Jurgen Klopp has certainly been impressed, saying recently: "If you lived and worked in Germany you would have known much more about him. It was pretty clear it would make sense to sign him.
"Tall players like him need physical fitness. He needed to create some physical strength, but there was never a doubt about his quality."
Liverpool currently sit second in the Premier League and it's thanks to some superb performances from Matip that they're challenging for the title.
Indeed, impressive victories over Arsenal, Chelsea and Leicester City - and draws against Manchester United and Tottenham - wouldn't have been made possible without Matip defending so valiantly against some of the league's finest strikers.
The Cameroonian has largely contained the likes of Harry Kane, Diego Costa, Alexis Sanchez, Jamie Vardy and Zlatan Ibrahimovic - and he's now named his toughest opponent so far.
In a widespread interview with the Liverpool Echo's James Pearce, he said: "There are a lot of tough players in this league.
"He didn't play well against us, but Costa is a great player."
Despite conceding against the Spanish striker, Matip dealt well with his threat at Stamford Bridge using his own strength and aggression.
Liverpool ran out 2-1 winners over Antonio Conte's side thanks to Lovren and Jordan Henderson's wonder strike, the Englishman firing home from 30 yards.
Matip appears to be enjoying life on Merseyside and explained how the best is yet to come following an injury-ravaged start.
"The beginning for me wasn't the best," he added. "I had the problem with my foot in pre-season but since then it's gone well. I have played a lot of games and I hope it will continue like this.
"It's an honour and a joy to play for Liverpool. It's a great club. I've been able to help the team get some good results and I am really happy to be here.
"Why did I settle so quickly? My teammates helped me from the first day I was here. That support meant I could play my game.
"I'm also playing for a great coach who improves every player he works with. I still think I can improve and I know I will get better."