Andre Agassi re-injured a chest muscle at the Eurocard Open, forcing a layoff that could cost him his No. 1 ranking.
Agassi said the injury, which first bothered him at the Davis Cup semifinal against Sweden a month ago, flared up again while he was serving in the first set against fellow American MaliVai Washington, who went on to win the match 4-6, 6-1, 6-1.
Doctors described the problem as a muscle strain.
Agassi, playing in his first tournament since that Davis Cup match, withdrew from a doubles match scheduled later and said he will be treated with ultra-sound, anti-inflammatories and ice.
The ATP Tour World Championship in Frankfurt will be held Nov. 14-19.
The first event Agassi will miss will be next week’s Paris Open, in which he is the defending champion.
The layoff means Agassi is likely to lose his top ranking to rival Pete Sampras, who is only 282 points behind.
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