Romania's Victor Hanescu stormed out of his Wimbledon third-round match after appearing to spit at the crowd in chaotic scenes on Friday.
Four fans were also arrested in an unrelated incident on Day Five of the tournament.
Hanescu, seeded 31, was trailing Daniel Brands 3-0 in the fifth and final set when he walked up to umpire Kim Craven and retired after being involved in an altercation with fans who were cheering loudly for his German opponent on Court 18.
"Someone said something in the crowd. We don't know what it was. He then appears to go and spit in the direction of those people," a Wimbledon spokesman told reporters about the incident.
"It was 0-2 at the time. He then has a service game in which it looks as though he deliberately served double faults.
"He also swore in the direction of the same people. A combination of the spitting and swearing gives him a code violation for unsportsmanlike behaviour and then he retires from the match," added the spokesman.
"He tried to shake the umpire by the hand, the umpire doesn't accept the shake and then he shakes his opponent by the hand and that's the end of the match."
Police also said four youths were arrested from the same court, site of the marathon 11-hour match between John Isner and Nicolas Mahut earlier in the week, but added the two incidents were unrelated.
"At approximately 2050 (local time) police were called to the tennis championships, four men were arrested under section five of the public order act (for disorderly behaviour) and they were taken to a south London police station and enquiries continue," said police.
Under grand slam rules, Hanescu faces a fine of up to $10,000 for unsportsmanlike conduct for the incident although Wimbledon officials said they would take their time to gather evidence since the Romanian is no longer in the tournament.
"Victor Hanescu retired from the match due to a leg injury. The Referee's Office is reviewing further information from this match. No further announcement will be made this evening," the All England Club said in a statement.
Last November, women's world number one Serena Williams was fined a record $175,000 and put on probation for two years for her foul-mouthed tirade at a lineswoman at the 2009 US Open. The fine will be reduced to $82,500 if she commits no further major offence through 2011.
