Roger Federer may have lost the tag of world number one but he is still a formidable opponent, several top players said on Monday.
The usually-composed Federer, who has yet to win a tournament in 2009, broke down in tears after losing the Australian Open final to the top-ranked Rafael Nadal in January and smashed one of his rackets in this month's Miami Masters.
"I found it strange he broke his racket in Miami, he who always keeps calm," world number three Novak Djokovic told reporters at the Monte Carlo Masters. "But these things happen when you are frustrated on the court.
"Federer won everything for four years and now he starts losing against some players but you cannot say he is in crisis."
Nadal said the Swiss, who starts his Monte Carlo campaign with a second-round match against Italian Andreas Seppi on Wednesday, had performed well this year.
"He has played a grand slam final and two Masters Series semi-finals, these are very good results," said the Spaniard.
"Everybody talks about the racket he smashed in Miami but that's nothing. It happens to everyone.
"He just needs a title to confirm his good start to the season."
Frenchman Gilles Simon, who beat the former world number one twice last year and has yet to lose to the Swiss, said Federer was still a class act.
"Why does he lose his temper on the court? Because he did not need to before as he used to slaughter everyone," said world number seven Simon.
"To me, on a good day, he still is the best player in the world. He had already broken rackets before, now he is frustrated so he does it again.
"In a way it makes him more human."
Spaniard Fernando Verdasco said world number two Federer was finding it difficult to cope with more regular defeats.
"Two years ago he was winning everything. Now, since the beginning of the year, he has been beaten by Nadal, Djokovic and (Andy) Murray," said the eighth-ranked Verdasco.
"I think mentally it is not easy to handle."
Gael Monfils, who lost to Federer in the French Open semi-finals last year, said the Swiss would be looking to avenge his defeats.
"We must not forget who he is," said the 10th-ranked Frenchman. "He will be out for revenge."