Andre Agassi [Images] has had another injection in his troublesome back as he looks to end his career on a high note at the US Open.

The 36-year-old American, who is due to retire after the tournament, had the injection on Tuesday, the day after his battling four-set win over Andrei Pavel of Romania in round one.

"To be honest, I couldn't even stand after the match," Agassi said in a television interview with USA network on Wednesday.

The unseeded American, who reached the final in New York last year, needed 3-1/2 hours to beat Pavel on Monday.

"An hour after the match it was really painful. I spent a good part of the day in the hospital yesterday getting an injection deep into my spine.

"(But) the alternative is for me to limp off the court in front of my favourite people in the world and that's something I don't want to do."

Agassi, who meets Cypriot eighth seed Marcos Baghdatis in the second round on Thursday night, looked good in practice at Flushing Meadows on Wednesday and said he was ready to battle it out again in round two.

"It was good. I have seen enough of the way he (Baghdatis) plays to know what he is like on paper, but you don't really know until you face up to it," he added.

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