David Nalbandian was disqualified from the Queen's Club final in London after injuring a line judge during the match on Sunday.
The 10th-seeded Argentine kicked the small barrier surrounding the line judge in anger after dropping his serve to Marin Cilic at 3-3 in the second set. A piece of the barrier then hit the line judge, causing bleeding on his left shin.
As a result Nalbandian, who had been leading sixth-seeded Marin Cilic of Croatia 7-6 (3), 3-4 when the incident occurred, defaulted the match.
Tournament director Chris Kermode said organisers had no option but to call off the final.
"He (Nalbandian) kicked the panel underneath the line judge, the panel went flying into his (the line judge's) leg. Cut his leg, he's actually quite seriously injured. Rules are rules. The ATP have forced us to end the final with a code violation,'' Kermode said.
"He has been taken up to the medical centre. David is feeling terrible, about what he did and how it happened.''
But Nalbandian was insisted that he should not have been forced to default the match.
"Sometimes you get very frustrated on court and it's tough to control that and sometimes I do a mistake, so it's very tough to end a final like that,'' he said.
"But sometimes we feel so much pressure from the ATP to play a lot of tournaments. They don't do anything to (for) us, and today I do a mistake and I have to pay like that.
"I agree I do a mistake but sometimes everybody do a mistake and I didn't feel it had to end like that, especially in a final.''
ATP rules state that any violent action will result in an automatic default.
"There is a lot of rules, and sometimes they (ATP officials) don't do anything. The rule book is very big and I can tell you that the ATP do a lot of mistakes to the players and nothing happens,'' Nalbandian said.
Cilic was disappointed to win the match by default.
"It's definitely not the way I wanted to win it,'' Cilic said.
"The match was still open but I can't change it. I'm sorry for the guys (spectators) that it had to end like this.
"We had some good rallies and it's hard to see the final end like this.''
Nalbandian was contesting his first final on grass since losing to Lleyton Hewitt at Wimbledon 10 years ago, and was bidding to become the first player from Argentina to win an ATP grass court title since Javier Frana triumphed in Nottingham in 1995.
The No. 10-seeded Nalbandian, whose last title came in Washington in August 2010, had made the more positive start, breaking with a crosscourt backhand to lead 1-0 and holding two break points for a 3-0 lead.
Cilic then settled and levelled at 3-3 when a lob from Nalbandian landed long, but the Argentine went on to take the set in a tiebreaker.
Cilic responded by breaking serve with a blistering service return in the opening game of the second set, but Nalbandian broke to level at 3-3, only to concede his serve again in the following game.