Rafael Nadal is back, and it's all about his back.

Top-ranked Nadal injured his back warming up for the final of the Australian Open almost three weeks ago, eventually losing against Stanislas Wawrinka — a match he was an overwhelming favorite to win.

Nadal has practiced little since then, getting treatment at home in Mallorca. His first test comes in next week's Rio Open, a new stop on the ATP Tour.

Nadal is cautious speaking about the back, saying: "we'll have to see how it goes. I hope I can tolerate it."