Ferrari's Spaniard driver suggests championship rivals are using ongoing tyre controversy as an excuse for slipping up in recent races.
Tough competition hard to accept for Red Bull, says Fernando Alonso
Three-time champion Sebastian Vettel again leads the way after the opening four grands prix and Red Bull are way out in front in the constructors' championship, but their voice has been the loudest when it comes to complaints about the Pirelli tyres.
Team principal Christian Horner, Vettel and teammate Mark Webber have all expressed their unhappiness at the state of this year's rubber.
Even owner Dietrich Mateschitz condemned Pirelli following the Spanish Grand Prix 11 days ago when he claimed Formula One had become "more about tyre management" than "real racing".
Ferrari star Alonso, who claimed the 32nd victory of his F1 career in Spain where Vettel and Webber could only finish off the pace in fourth and fifth, feels such comments are sour grapes now Red Bull's dominance has slipped.
"We know Barcelona was a good race for us and not so good for some of our competitors," said Alonso, speaking ahead of Sunday's Monaco Grand Prix.
"Some of these competitors claim to have a super car, but the last three pole positions have been taken by another car [Mercedes] when the tyres are new.
"It sometimes happens when you win too easily for some years it then becomes difficult to lose some races."
Following a race that incorporated 79 pit stops in Barcelona, Pirelli are to make changes to the structure of the tyre for the next event in Canada early next month.
It has been suggested such changes will not be as extreme as first thought, and so perhaps not favouring Red Bull as much as they may have hoped.
Alonso is holding fire on passing judgment until he samples the new tyres in Montreal.
"We are still awaiting the final specification of the changes, so there is still a bit of a question mark at the moment," he said.
"There were some ideas about changing, then maybe less, and now we don't know exactly what the changes will be.
"So when we have the exact characteristics, and probably after the first race with those tyres, we will maybe have more of an idea."
For now, Alonso heads into F1's blue ribbon event high on confidence and determined to end Ferrari's 12-year wait for a win around the most famous street circuit in the world.
"Obviously we want to win the championship, but Monaco is a special race, the most important in the championship," said Alonso, a prior two-time winner with Renault and McLaren at this track.
"Everyone in any country has heard about the Monaco Grand Prix, the Indy 500 and Le Mans. They are the three races motorsport fans and non-motorsport fans know about.
"Now we are in Monte-Carlo and it's many years since Ferrari has won here.
"For me personally I can be the first man to win for three different teams, so my motivation is high to do it."
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