Novak Djokovic insists he will only play at Wimbledon if he is fit enough to compete for the title.
Djokovic is recovering from knee surgery to repair an injury sustained at the French Open earlier this month.
It initially looked as if the seven-time champion had no chance of competing at this year's tournament, but he has made rapid progress and had a two-hour training session at Wimbledon's Aorangi Park on Monday.
Djokovic says he will make a decision before Friday's draw.
"I didn't come here to play a few rounds," he told BBC Sport.
"If I know I can play close to my maximum or at maximum, then I'll play. If not, then I'll give somebody else a chance to play.
"I really will only play if I know I am in a state which is good enough to go far in the tournament and fight for the title, so that's the condition.
"Rehab is going in the right direction every single day, a few per cent better and better. That's what's giving me hope and encouragement to keep going.
"I'm taking things gradually. I'm not pushing myself yet 100 per cent but I'm hoping that's going to come in the next few days."
Djokovic's long-time rival Andy Murray is also in a race to be fit for the tournament, having undergone back surgery last Saturday.
Murray, who was prematurely ruled out of the tournament, is set to decide in the coming days.
