Aching joints and muscles are nothing new on the men's and women's tennis tours, but the injury bug seems to be biting even more than usual this year.
Here's a quick recap of some of the problems the top players have been experiencing this season.
Rafael Nadal -- Suffered a back injury in the Australian Open final, and, although he says it hasn't bothered him for a while, Nadal hasn't played his best since.
Novak Djokovic -- Suffered a wrist injury before Monte Carlo, which was identified by his physiotherapist as an inflamed tendon. Gave him no problems in Rome after two weeks of treatment and rest, but now he must try to avoid aggravating it.
Stan Wawrinka -- Tweaked his back slightly at Rome, although he insists it will not be a problem for the French Open.
David Ferrer -- Experienced a groin injury that kept him out of Indian Wells, but tests showed no tear and he has looked fit since.
Juan Martin del Potro -- Expected to be out for months after undergoing surgery on his left wrist.
Milos Raonic -- An ankle problem affected him at the Australian Open and kept him out of Davis Cup, but he has returned strongly.
Kei Nishikori -- Withdrew from the Miami semifinals with a groin problem and retired in the Madrid final with a back injury that also kept him out of Rome, but is expected to return at the French Open.
Richard Gasquet -- Has not played since Miami with a back problem, which has improved after extensive treatment but only just allowed him to start hitting balls again. Questionable for the French Open.
Tommy Haas -- The shoulder that repeatedly has required surgery is again giving him problems, including a quarterfinal retirement at Rome a week ago.
John Isner -- Went out of the Australian Open with a foot injury and withdrew from doubles at Madrid with a back problem.
Fabio Fognini -- A right quad problem has affected him throughout the season, perhaps a reason for some of his frustrated performances recently.
Mikhail Youzhny -- Withdrew from Indian Wells with a back injury.
Santiago Giraldo -- Had a hip flexor injury at Rome.
Nicolas Almagro -- A leg problem has affected him in the clay season, including a withdrawal at Rome.
Philipp Kohlschreiber -- has been having an elbow problem, although it hasn't kept him from playing.
Florian Mayer -- A hip injury is expected to keep him out of the French Open.
Gael Monfils -- Withdrew at Nice this week with a persistent ankle problem, saying he could not move well enough for singles, and could be hampered in the French Open.
Benoit Paire -- A persistent knee injury has kept him out of tournaments and caused him to withdraw at Nice this week.
Jurgen Melzer -- Had to withdraw from Acapulco after returning from a shoulder injury, which kept him out until the clay season.
Vasek Pospisil -- Has been experiencing back problems since the start of this season.
Lleyton Hewitt -- Had problems with his shoulder after the Australian Open, but has played regularly since.
Bernard Tomic -- Was booed after retiring to Nadal at the Australian Open, had double hip surgery, got defeated in record time in his first match back and hasn't won since.
Serena Williams -- A back problem affected her at the Australian Open, and a thigh injury at Charleston and Madrid, but then she swept to the title at Rome a week ago.
Victoria Azarenka -- Has not played since the Australian Open with a foot injury and has withdrawn from the French Open.
Agnieszka Radwanska -- A shoulder injury affected her in the Indian Wells final, but she has played regularly.
Simona Halep -- Withdrew from Rome with an abdominal injury and is still adjusting her schedule after becoming a top player.
Angelique Kerber -- Retired at Madrid with a back problem but says she is finding her rhythm again.
Sara Errani -- Was affected by a hip flexor injury in front of her home fans when playing the final at Rome.
Caroline Wozniacki -- Withdrew from Stuttgart with a wrist injury and had knee problems in Madrid that kept her out of Rome.
Ana Ivanovic -- Suffered a hip injury in her run at the Australian Open, but has returned strongly.
Sloane Stephens -- Ongoing wrist problems at the start of the year.
Svetlana Kuznetsova -- Withdrew from Rome with hip injury.
Maria Kirilenko -- Returned at Charleston from a knee problem, only to experience a wrist injury that caused her to withdraw at Madrid.
Bethanie Mattek-Sands -- Underwent hip surgery about a month ago.
Laura Robson -- Underwent wrist surgery about a month ago.