Rafael Nadal is hopeful of being able to compete at the ATP Finals in London.
The Spaniard suffered an abdominal injury at the Paris Masters last week and had to pull out prior to his scheduled semi-final against Denis Shapovalov, prompting concerns he may again miss the season-ending showpiece.
Writing on Twitter, Nadal said: "Despite having a small strain, I will travel to London. Thursday or Friday I will start serving. The idea is to be able to play the #atpfinals in London."
Nadal has pulled out of the ATP Finals four times since it moved to London in 2009 while he withdrew after one round-robin match on his last appearance in 2017.
The 33-year-old regained the world number one ranking for the first time in a year on Monday but has Novak Djokovic breathing down his neck in the race for the year-end top spot.
Nadal, who has never won the title, would need to reach the final and win all three of his group matches to guarantee staying at number one.
The draw for the tournament takes place on Tuesday afternoon.