Former Liverpool captain Sami Hyypia has hailed the impact of summer signing Joel Matip.
Hyypia has been impressed with the ex-Schalke centre-back following his free transfer to Anfield this summer.
Hyppia, who came up against Matip in the Bundesliga while manager of Bayer Leverkusen, believes the 25-year-old has all the qualities you want to see from a central defender.
"I knew him from Germany, I think I played against him and then managed Leverkusen when he was at Schalke," he told Liverpool's official website.
"He's a good player. He's a big guy, dominant player, very comfortable on the ball and that's a big piece of how the team plays.
"When you want to play football, you need to have somebody who is comfortable on the ball and on the other hand a strong defender.
"His style of play is that he is comfortable on the ball but I think that comes from confidence, he is very confident that he can play football."
Meanwhile, manager Jurgen Klopp has dismissed the notion that Matip is the solution to all of Liverpool's back four troubles.
The Cameroon international missed the 4-3 defeat to Bournemouth on Dec. 4, but Klopp believes Matip would not have been solely able to prevent the comeback.
"When you concede four at Bournemouth ... that was bad defending," Klopp said. "You could see it.
"But afterwards it was 'ah, we missed Matip, we missed the centre half.' Joel Matip would not have stopped that fourth goal. Would he have run from the six-yard box to stop the shot? No. It would have been exactly the same.
"We made mistakes, didn't feel comfortable, didn't push up. That is defending."
Liverpool have conceded 20 goals in the Premier League this season -- four more than Wednesday night's opponents Middlesbrough, who lie 16th in the table.
"If I wanted perfection, I could point a finger here, there, everywhere. Managing is not like this. We have to see the whole picture," Klopp added.
"You can pick out single situations, maybe someone else can point out another. We could talk about it, if you would not make big things of it.
"It only helps if we all do better. If I put a new goalkeeper in for example and we let them shoot from there and there, it doesn't change
"We have to avoid situations like this as a team, and we do it well. That is why when we speak about our defence problems, and people suggest that we are actually not so bad at defending, I already knew this.
"But of course we still concede goals, and then people then ask for other players. My job is to work with the players and make sure we have the right balance and consistency.
"We have improved a lot in a lot of parts of defending, yet we are still conceding. Sorry!"