Novak Djokovic is yet to confirm if he will compete in this week's Monte Carlo Masters.
The world No 1 injured his right ankle during a recent Davis Cup tie against American Sam Querrey.
Although the news is good regarding the injury - an MRI scan revealed no structural damage to the joint capsule and ligaments - the strain still requires considerable rest.
The Serb suffered the injury early in the match but carried on to win in four sets.
Djokovic admitted: "I can't guarantee 100 per-cent that I'll be on court. I have to be realistic and cautious.
"I've had three days of practice and I've been increasing the level each day.
"If I have discomfort over the next two days that would be an indication.
"This is the start of a new season on a new surface. To compete at a high level I must be 100 per-cent fit.
"I've been taping the ankle and doing all I can to be ready. I know there is a lot of expectation for me to play and no one wants me to be out there more than I do.
"I consider this a very special place and I'm extra-motivated. I'm really encouraged by the progress over the last few days, it's much more than I would have expected it to be. I'll do everything in my power to play."
The six-time Grand Slam winner could be allowed to start his campaign as late as Wednesday in order to give him every chance of taking part in this prestigious event.
The top seed's first round opponent on clay will be either Russian Mikhail Youzhny or Daniel Gimeno-Traver of Spain.