The January transfer window, a chance for clubs across Europe to bolster their squads ahead of the second half of the season, is about to swing open. In the Premier League, in particular, all the prizes remain firmly up for grabs and several teams have obvious weaknesses, meaning there could be some major activity at the start of 2015. Here are five players likely to be in high demand over the next month:

Mats Hummels (Borussia Dortmund)
Quality center-backs in the world are few and far between in this attack-centric era, which explains why there has long been such a clamor over Mats Hummels. The German World Cup winner is a calm and collected presence at the back and assured on the ball, although he can be exposed at times, as he has been more often than he’d like in recent months. He has repeatedly insisted he has no intention of following the likes of Mario Gotze and Robert Lewandowski out of the Dortmund exit door, although speculation has increased following his club’s disastrous start to the season.

Rumors: Both Arsenal and Manchester United are on the lookout for center-backs and Hummels is reported to feature high on both of their lists of targets. United were also linked strongly to the 26-year-old in the summer.

Prediction: With Dortmund sitting in the Bundesliga relegation zone, the future of several of their big names must be in doubt. However, they remain in the Champions League and will be loathed to lose anyone in midseason.

Lucas Silva (Cruzeiro)
One of the more fundamental reasons for Brazil’s disastrous World Cup was their failure to produce a quality passing midfielder in recent years. In Lucas Silva they may have someone who can fill that role in the coming years. Orchestrating play from deep, the 21-year-old has helped Cruzeiro to two straight Brasileirão titles and was recently voted the league’s best defensive midfielder for the past season.

Rumors: Real Madrid have been strongly linked with a January move and  manager Carlo Ancelotti has admitted he has an interest in the player. Arsenal and Manchester United are also said to be keen

Prediction: While Arsenal and Manchester United could do with a holder in midfield, Real Madrid looks by far his likelier destination. Whether the move goes through in January could well depend, as Ancelotti has suggested, on the fitness of Luka Modric and the future of Sami Khedira.

Kevin Strootman (Roma)
The all-action midfielder was pivotal to Roma’s flying start to last season, before his campaign was prematurely ended by a cruciate ligament injury that also forced him to miss out on the 2014 World Cup with the Netherlands. The 24-year-old has only recently returned to the first-team with the Italian club and has understandably yet to get back to his best.

Rumors: Strootman has been mentioned in connection with a transfer to Old Trafford since long before he made the move to the Italian capital. Unsurprisingly, the intensity of the rumors have increased since Van Gaal, who valued Strootman highly when in charge of the Netherlands, took over. Roma’s recent Champions League elimination is said to have increased the chances of the deal happening in January.

Prediction: Roma continue to insist that they have no intention of allowing Strootman to leave, despite bowing out of the Champions League. While the Serie A club’s owners have shown a desire to do a deal for the right price before with their players, it remains doubtful that United would be willing to pay the in excess of £30 million it will likely to take to prize away a player who is still some way short of getting back to his best.

Edinson Cavani (Paris Saint-Germain)
His massive transfer from Napoli in the summer of 2013 always appeared odd given the presence of Zlatan Ibrahimovic at Paris Saint-Germain, and the situation has panned out as expected, with Cavani forced to operate from a wide position. The Uruguay international, a prolific scorer in Italy, has still scored at a decent rate in France, but his form has certainly dipped in recent months.

Rumors: Cavani has suggested that he isn’t exactly happy with his role in the team and his recent absence from Paris Saint-Germain’s winter training camp in Morocco has sparked further rumors about a move to the Premier League. Arsenal have been most strongly linked, although Manchester City might also be keen having previously pursued his signature.

Prediction: PSG coach Laurent Blanc on Wednesday refused to rule out Cavani’s departure, and, restrained by Financial Fair Play restrictions, there is a sense that they would sell should they receive a big offer. Yet, with Cavani not in the best form, it is difficult to see who would be prepared to put up the cash. Despite the continued speculation, Arsenal’s priorities surely lie elsewhere.

Wilfried Bony (Swansea City)
It is no surprise that every top Premier League side in need of a goalscorer has been linked with the Swansea striker. After an impressive first season in England, Bony has eight goals to date this campaign and is a formidable presence leading the line. Still, Swansea continue to insist that they haven’t received any offers for the Ivorian. Certainly they wouldn’t welcome any.

Rumors: It would almost be easier to name the major clubs not to have been credited with an interest in Bony. Chelsea are the latest club to join a list of rumored suitors that already includes Liverpool, Tottenham and Manchester City.

Prediction: Swansea are thought to be after between £25 million and £30 million, which would likely deter any bids. It may take Bony, himself, to demand a move in order to lower the asking price, something which is likelier to happen in the summer.