* Ferrero loses in first round to close friend Almagro
* Tsonga pulls out of Malisse match with back pain
* Tipsarevic also pulls out with shoulder problem (Updates with Tipsarevic injury)
VALENCIA, Spain, Oct 23 (Reuters) - Carlos Ferrero's singles career drew to an emotional end when he lost 7-5 6-3 to fellow Spaniard and close friend Nicolas Almagro in the Valencia Open first round on Tuesday.
A former world number one who won the French Open in 2003 but was hampered by injuries throughout his career, Ferrero announced last month he would retire after playing his home event.
Sixth seed Almagro, 27, Ferrero's junior by five years, had too much power and speed for his mentor in an entertaining match in which the pair exchanged smiles and jokes.
The younger man seemed to be suffering from a right shoulder problem late in the second set but shrugged off the injury and sealed victory on his first match point when wildcard Ferrero netted a return.
The pair embraced at the net and the 32-year-old was given a rousing ovation by the crowd as he fought back tears before flinging his racket, shirt and various other personal items into the stands.
"It's been a long time since I enjoyed myself so much on a tennis court," said Ferrero who will join up with singles top seed David Ferrer in the doubles on Wednesday.
"It was an honour to finish my career playing you, I think you are a great champion," he told Almagro whose coaching staff he will join on a part-time basis next year.
"I simply want to thank everyone for all their support, not just this year but throughout all the years I have played here," Ferrero said. "It's always been a very special tournament for me and this year even more so."
Almagro paid tribute to his friend.
"Maybe it was the most bitter win of my career as a great tennis player is leaving us," he said.
"I hope he'll be with me for a few weeks next year and I think we'll have some fun. I still have a lot to learn from him."
World number five Ferrer, who has already qualified for next month's season-ending ATP Tour finals in London, battled past Belgian qualifier Olivier Rochus 7-5 7-5.
Second seed Jo-Wilfried Tsonga's chances of qualifying for the finals were dealt a blow when he pulled out of his first-round match against Xavier Malisse with the unseeded Belgian leading 3-1 in the opening set.
It was a similar story for third-seed Janko Tipsarevic who also withdrew from his match against unseeded Giles Simon when 5-4 down, as he suffered a problem with his right shoulder.
With two spots still available in the race for London, Argentine Juan Martin del Potro is seventh, Frenchman Tsonga is in the eighth and final position, and Serbian Tipsarevic is ninth.
Ferrero turned professional in 1998 and went on to win 16 titles including the Masters events in Monte Carlo and Rome.
As well as his sole grand slam triumph at Roland Garros, he reached the final there in 2002 and the U.S. Open final in 2003 after which he rose to world number one and stayed there for eight weeks.
Ferrero's last title came in Stuttgart in 2011 on his favoured clay surface. He has slipped to 161st in the latest singles rankings.
In an interview with As sports daily published on Tuesday, he said it was hard to choose the toughest opponent he had faced but Australian Lleyton Hewitt, another former number one who is competing in Valencia, was one of them.
He added he had learned a lot from retired American Andre Agassi in terms of his attitude on the court, his training regime and his "professionalism", but Roger Federer was the player who had impressed him most.
"You feel that he can do anything and that you are missing that little bit," he said of Federer. "He is the only tennis player who has made me feel inferior."
Ferrero played in 17 Davis Cup ties for Spain, compiling an 18-6 record in singles rubbers, and helped them to their first triumph in the competition in 2000 and subsequent victories in 2004 and 2009.