It's no surprise that Liverpool have been struggling since Virgil van Dijk went down with a long-term injury in October.
The Reds don't look the same team without Van Dijk at the back.
And that's understandable given the Dutchman is the greatest defender in the world.
Van Dijk has frustrated a number of the best forwards in the world in the past few years, including Wilfried Zaha.
Speaking on Jamie Carragher's the Greatest Game podcast, Zaha was full of praise for the Liverpool star.
“He’s fast, calm, strong. He’s got everything,” he said, per the Liverpool Echo. “Obviously Rio [Ferdinand] was just composed to the next level, but I feel like Virgil has everything down to a tee.
"Like to the point where he can muck about when a ball comes over the top and flick it around the striker and stuff and he’s fast enough to get back on to it.
“When we play against Liverpool it’s like, how am I going to get around this guy?”
Zaha isn't the only forward that have summed up Van Dijk's brilliance after playing against him.
Eight other forwards have sung his praises, including Lionel Messi and Sergio Aguero.
Lionel Messi
Messi came up against Van Dijk when Barcelona met Liverpool in the Champions League semi-finals in 2019.
He later spoke about the encounter in an interview with Marca.
“He is a defender who knows how to judge his timing and wait for the right moment to challenge or jockey [the attacker],” Messi said.
“He is very fast and big, but he has a lot of agility for his height.
“He is fast because of his great stride, and he is impressive both in defence and attack because he scores lots of goals.”
Sergio Aguero
Aguero is one of the best strikers in Premier League history but even he struggles with Van Dijk.
"We all know Van Dijk is one of the best centre-backs in the world. He's strong, tall, has an incredible body," Aguero told El Chiringuito, per Goal.
"He's very strong face to face, he plays with his body. Also, given he is so tall, he has those long legs.
"It looks like he isn't fast but he is, because of his long legs - he can reach everywhere. Two steps from him are 50 for me!
"What I like the most is the way he is so smart when defending. He's not anxious when marking, he's very careful and patient. That makes it difficult for many strikers."
Erling Haaland
Haaland came up against Van Dijk when he played for RB Salzburg in 2019.
Van Dijk left a big impression on the youngster.
“He is so good,” Haaland told France Football. “He is powerful, quick, he possesses all the qualities. He is an incredible player."
The Norwegian recently named Van Dijk as one of the three best defenders in the world, per AS.
Alvaro Morata
Morata named Van Dijk as one of the three best defenders in the world in an interview with AS.
His description of the Dutchman was brilliant.
He said: "When you go against Van Dijk it seems like you hit a mountain."
Troy Deeney
Deeney has said numerous times just how good Van Dijk is.
“I've said it many times, I hate him,” he told BBC Radio 5 Live in 2018, per the Daily Mail. “I hate going up against him.
“He's too big, too strong, too quick, too good on the ball, loves fighting, a good head of hair.”
Tammy Abraham
Abraham labelled Van Dijk a 'beast' and said he was 'annoying' to come up against.
"He’s a beast. He’s just good at what he does. He’s experienced. His understanding of the game is top drawer,” Abraham said, per the Liverpool Echo.
"It is to do with little things. Movement. My movement in the box, some defenders don’t pay attention to me - they are only focused on the ball.
"With him, it’s kind of both, he’s paying attention to me and the ball, knows where I am, knows where I want to go, follows me.
"It’s quite annoying for a striker - just leave me alone!"
Glenn Murray
Brighton's Murray said that Van Dijk 'treated him like a boy',
“First and foremost, he is just a man mountain, isn’t he?! I mean he treated me like a 12-year-old boy. He just moves you out of the way.” Murray told Sky Sports.
“When you put somebody in defence and he makes those around him better, I think that’s the real test of a true great.
“He’s been such a huge signing for them.”
Oli McBurnie
Sheffield United's McBurnie said Van Dijk was so strong that he felt like 'a little girl'.
"It took me a few months to get up to speed,” he said, per the Sheffield Star. “I had to do gym for the first time in my life!
"I bounced off van Dijk and realised I needed to do a bit of bench press. He had everything and I felt like a little girl against him.
"I'm skinnier than a lot of defenders so when the ball goes up in the air, I give them a nudge in the air and that's always worked, at any level.
"I tried it with van Dijk. He was off-balance, and I still bounced straight off him. I thought: 'I'll have to go and play off Joel Matip here instead!'."
Van Dijk's return couldn't come soon enough for Liverpool.
He really is something else on the football pitch.