With two weeks left until the European transfer window closes, plenty of managers will be monitoring the fitness of their playing staff closely to determine whether injuries indicate new signings are needed.
The successful modern-day football squad is built to withstand the loss of a handful of players to knocks and strains, of course, but a spate of long-term injuries—or even a single one to a key player—can have a severely detrimental effect on a team reaching their seasonal objectives.
Here's a latest look at how some of the biggest names in the game are recuperating at present from their injuries and when they should be back in action.
—Updated Jan. 17, 5:30 a.m. ET—
Wigan Athletic, battling relegation in the Premier League, will have to do without key central defender Ivan Ramis for the remainder of the season.
He has suffered a ruptured anterior cruciate ligament, sustained in the recent match against Fulham, and will be out for between six and nine months.
Wigan have conceded 40 goals this season, the joint-third-worst in the division, and will miss the organisation as well as the defensive ability of the Spanish defender.
In Germany, Schalke 04 defender Kyriakos Papadopoulos has been recuperating from a knee operation since mid-December.
Though no official timescale has been set for his return, he is expected to be fit once more in the next six weeks. Schalke are currently seventh in the Bundesliga.
He has played 10 league games so far this season, scoring once.
Finally, over in Spain, Getafe's Pedro Leon should be making his comeback shortly from a knee sprain suffered in December.
He was expected to miss around a month or so, having earlier this season missed six weeks because of a knee cartilage problem which required surgery. Injuries have restricted the on-loan Real Madrid winger to just 15 appearances this season.
Arsenal's key midfielder Mikel Arteta is currently sidelined with a calf strain.
The knock was picked up in training and caused him to miss the recent 2-0 home defeat to Manchester City—and he is set to miss a further three weeks more (per BBC).
Manager Arsene Wenger certainly has plenty of players in his squad who can fill the role of Arteta, namely the returning Abou Diaby and Aaron Ramsey, but Arteta is very much a first choice and has been the most consistent Gunners midfielder this season.
Ramsey has played much of this season out on the flanks, while Diaby has struggled with his own injuries this year once again.
If he misses the full term of three weeks, Arteta could miss further fixtures against Swansea (FA Cup), Chelsea, West Ham, Liverpool and Stoke City.
Arsenal's opponents on Sunday, Manchester City, were missing their own big-name star in striker Sergio Aguero.
Having injured his hamstring against Stoke on Jan. 1, Aguero is racing against the clock to be fit for the Fulham match, according to manager Roberto Mancini (via MCFC.co.uk).
Edin Dzeko has been in good form of late, and with Carlos Tevez and Mario Balotelli also available, it is unlikely Aguero will be risked if he is not fully fit, but the Argentine should at worst only miss one more league game.
New Fiorentina signing Giuseppe Rossi is still sidelined with a long-term injury that has kept him out for over a year now.
The Italian international injured his cruciate ligaments while playing for Villarreal in 2011 and suffered a setback six months later which required further surgery. He is not expected to resume training until March.
Fiorentina paid around €10 million to take Rossi back to Italy (via Goal.com) during the January transfer market, gambling on a full return to form after he recuperates completely, which will make the outlay seem like a real bargain.
AC Milan's tough-tackling midfielder Nigel de Jong will play no further part in his debut season in Italy, having suffered a ruptured Achilles' tendon (per Sky Sports).
The Dutch midfielder played 12 times in Serie A for Milan, scoring once, prior to sustaining the injury in early December.
He took the injury during a game against Torino, coming off early in the fixture, which Milan went on to win 4-2.
Recovery time for an Achilles' injury can range up to six or even nine months.