With days to go until the January transfer window, we look at four clubs who could change their season with one signing.
Arsenal - Ibrahima Konate
Gabriel has been a key figure in Arsenal's backline this season, but he's lacking a real defensive partner.
David Luiz and Rob Holding have failed to maintain any real consistency so far this season, hence, it would be a good idea for Mikel Arteta to make a move for a new centre-back capable of operating on Gabriel's wavelength - one such defender would be Leipzig's Ibrahima Konate.
Konate, 21, has only featured in six Bundesliga games for Leipzig this season, with the club's manager, Julian Nagelsmann, preferring Marcel Halstenberg, Dayot Upamecano and Lucas Klostermann over Konate.
But despite his lack of playing time, Konate is highly rated in Germany, so much so that he's expected to cost Arsenal a fee in the region of £54m should they try to sign him.
He's widely believed to be one of the best young centre-backs in Europe. He's 6'3, strong with the ball at his feet, and he's even been likened to Liverpool's Virgil Van Dijk because of his sentinel-esque defensive presence.
Being 21, he'd be a great signing for the future, but judging by his skill level, it's fair to say that he can come to the Emirates and make an instant impact.
Chelsea - Erling Haaland
Chelsea is in dire need of a consistent goalscorer. The Blues have scored just six goals in their last eight games - and their lack of a real goalscoring frontman has sent them plummeting down the Premier League table as they currently sit in 9th-place.
The good news is Chelsea is only five points away from fourth-place, thus, a good run of games could catapult them right back into a Champions League spot.
However, for Chelsea to hit a rich vein of form, they will need to solve their lack of goalscoring prowess, and by the looks of things, the quickest way for the Blue's to improve their output is by bolstering their attack with a proven world-class striker, and in that regard, one striker they could sign is Dortmund's Erling Haaland.
Haaland is arguably one of the best strikers in Europe. Dortmund is currently going through a rut, but despite his side's poor performances, Haaland has maintained his goalscoring form.
He's scored 14 goals in 12 starts for Dortmund, contributing nearly half of league goals. He's exactly the type of striker Chelsea needs - one who can convert his chances regardless of his team's form.
Haaland certainly won't come cheap, but considering how poorly Chelsea is performing, he'd be worth the risk of paying a hefty fee.
Tottenham - Emi Buendia
Emi Buendia is one of the most highly rated midfielders in the Championship.
Last term, Buendia proved to be a shining star in a rather dim season for Norwich, and he's now carried those impressive performances to the Championship, attracting the interest of Mikel Arteta.
Buendia has scored seven goals and registered six assists in 21 appearances for Norwich- only two other players have more assists than Buendia in the Championship this season.
Son Heung-Ming and Harry Kane both account for 24 out of the 33 goals Tottenham has scored this season - while the contributions from both players will be key for Spurs' title push, Jose Mourinho cannot afford to be over-reliant on the due going into the final months of the season.
Mourinho needs to sign a player who can make an additional impact in the attacking third, in a bid to further bolster Tottenham's chances of securing a top four finish.
Everton - Isco
This season represents Everton's best chance of securing their first top-four finish since the 2004/2005 Premier League campaign. The Toffee's currently sit in 6th-place, two points away from 4th-placed Liverpool with two games in hand.
But with the likes of Tottenham, Chelsea and Arsenal also gearing-up for a top-four finish, Carlo Ancelotti needs to make a quick foray into the transfer market in a bid to strengthen his side's chances of securing a top four finish - and with reports suggesting that Isco is out-of-favour at Real Madrid, it would be wise for Ancelotti to make a move for the Spaniard.
Isco's career at Madrid has been marred by a lack of playing time. He's one of the most technically gifted midfielders in the world, and under the right conditions, he could thrive beyond measure.
Carlo Ancelotti has already built a pretty strong set-up at Goodison Park, adding Isco to the fray would further solidify his side's potency going forward, allowing Everton to compete with the "big teams" for a place in next season's edition of the Champions League.