By Andrew Benson
Ferrari will be a weaker team as a result of signing Felipe Massa, ex-Formula One driver John Watson says.
Massa has not been impressive in his three years in Formula One
The Brazilian has replaced BAR-bound Rubens Barrichello and is a "stop-gap" until Michael Schumacher retires, five-time winner Watson told BBC Sport.
Massa was the "best available driver" because no top name would be prepared to be subservient to Schumacher.
Watson added: "He's their best option. Whether the team is weaker as a result of Barrichello going, I suspect it is."
Eyebrows have been raised following the world champions' decision to pick Massa because he has achieved little in three years racing in F1 with Sauber.
He was outpaced by team-mates Nick Heidfeld and Giancarlo Fisichella in 2002 and 2004, and after a bright start to 2005 has suffered a similar fate in recent races at the hands of Jacques Villeneuve.
But Watson, whose career stretched from 1974 to 1985, said Ferrari were suffering the consequences of a policy in which the team have been totally dedicated to Schumacher since he joined in 1996.
"Ferrari have got a problem in that there is no (top) driver who is prepared to sit behind Michael for a period of unknown duration, whether it's one year or six years, for the chance of being the leader," said Watson, who was runner-up in the world championship in 1982.
"This is the consequence of the policy that Ferrari have followed.
"As long as Michael is under contract there is no chance of any other driver coming in and being given equal status. So Ferrari's options, in reality, are very restricted.
"They could go with an unknown, but probably the most logical thing to do is what they have done, which is take someone who they do have experience of from the year's testing he did in 2003, and who, while he is a very quick driver, I have never been able to work him out.
"Obviously he's capable, but he looks like a chubby kid. He used to drive like an on-off switch.
"I think he's calmed down a lot. But when you go into a top team, it doesn't always follow that you're going to make a huge leap forward in performance.
Massa (right) will be expected to support Schumacher
"What Massa will find is, in the case of the car not being as good as he expects, if he continues in the basic style of driving he has, it will cause him trouble. He will not make progress."
Watson said Massa should forget any illusions about being able to challenge Schumacher.
"If he doesn't fulfil Ferrari's needs, in other words if he thinks he's going to take on Michael and beat him, he will be very quickly dumped," the 59-year-old former McLaren and Brabham driver said.
"What has become abundantly clear is people are always underestimating how good Michael is.
Probably a fairer judgement of where Ferrari are is where Rubens is - Michael is lifting the car and delivering performances above and beyond where the car is."
Barrichello, who joined Ferrari in 2000, terminated his contract a year early to take up an offer from BAR that has not yet been officially confirmed.
And Watson said he understood why the 33-year-old Brazilian had left.
"Barrichello clearly has an opportunity - probably his last one - to be a stand-alone team leader in a competitive team," he said.