Tim Henman has been accused of bad sportsmanship and described as "the worst rubbish there is" by Argentine David Nalbandian.
Henman and Nalbandian exchanged words over a line call
Nalbandian beat Henman 6-2 2-6 7-5 at the Madrid Masters on Thursday, and at one point the pair exchanged angry words over a disputed line call.
Speaking after the match, Henman said: "I think he's in a dream world."
Nalbandian responded: "All this selling himself as a gentleman is not true. He is the worst rubbish there is."
When serving in the final set, Nalbandian had a first serve called out but thought he should have had another two serves.
Henman was asked for his opinion and said it was probably in.
The Briton later explained: "He said 'well, you didn't give me first serve'. First serve at 5-5, 15-30 when I think your serve was in? I think he's in a dream world.
"Then he started questioning my sportsmanship, but if we go down that road there is only going to be one winner."
On a bad evening for Britain, Andy Murray admitted that his stunningly successful year is starting to take its toll after defeat to Novak Djokovic at the Madrid Masters.
The 19-year-old led by a set and a break before losing 1-6 7-5 6-3.
"A combination of mental fatigue and my serve not holding out were the reasons for my defeat," said Murray.
"Mentally, I'm struggling. Maybe after playing around 26 tournaments I'm not used to playing all the time at such a high level."
Murray added that a meeting with Real Madrid star David Beckham had proved inspirational.
"It was nice to see him as he is one of the biggest sporting icons ever and is so polite and humble," said the Scot.
"It's good to see the way he has handled all the attention and criticism when I'm not likely to get even a tenth of that in my career."