Agassi said he would weigh up his future at the end of the season

The 35-year-old was due to play for the first time since the French Open in May when an inflamed sciatic nerve meant he limped out in the first round.

"It's not an easy time for me," said Agassi, who now plans to return in Los Angeles on 25 July.

"I have not responded to my cortisone injection as quickly as I hoped, so I had to slow down my preparations."

Agassi had a similar injection during the off-season but the injury flared up again as he lost in five sets to Jarkko Nieminen at Roland Garros.

The eight-times Grand Slam champion revealed that he can only have three or four injections a year and plans to have his third at the end of July to carry him through the US Open.

"While I know that taking injections is not a way of life, I'm only looking at a few years, so that's a reasonable approach towards it," he said.

I'm looking towards sizing everything up at the end of the year Andre Agassi

The veteran American said he would weigh up his future in the sport at the end of the season.

"When I am healthy and I am feeling good on the court, I still feel I can tap into parts of this sport that are beautiful to be a part of," he said.

"But while this is something I love doing, it comes with more of a price and for my family and all of those that make it possible for me.