Juan Pablo Montoya raced against Felipe Massa in Formula One for four years and it was plenty of time for him to form an assessment of the ability of Lewis Hamilton's rival for this year's world title.
Massa has emerged as Ferrari's leading contender this season
Montoya, a former Williams and McLaren driver now racing in the American Nascar series, was asked recently whether Massa had the talent to be world champion.
"Next question," he said. "We'll skip that one."
Montoya's evasiveness reflected an apparently widespread belief that it would somehow not be quite right if Massa overhauled Hamilton's seven-point advantage in the remaining Brazilian Grand Prix and won this year's drivers' title.
The general perception of the Brazilian throughout F1 is pretty straightforward - he's quick, but a bit wild and unpredictable, and too lacking in consistency and all-round qualities to be considered truly out of the top drawer.
But how fair is that assessment?
One man in a better position to judge than most is Honda team principal Ross Brawn, who was technical director at Ferrari during Massa's first season as a race driver for the team in 2006, as well as when he was their test driver in 2003.
In the year I worked with him at Ferrari, we had our ups and downs but I think Felipe has come on a long way
Honda team principal
"I think he would be a worthy world champion," said Brawn. "There is no issue there.
"He has been a bit of a slow grower, really, in that he was quite reckless and made a lot of mistakes early in his career but he was always very quick.
"In the year I worked with him at Ferrari, we had our ups and downs during the year but I think he has performed extremely well. Felipe has come on a long way."
The question, though, is how far? Does Massa yet deserve a place among the sport's elite or is he merely a very good F1 driver who has found himself in the best car and made the most of his chance?
Massa's supporters are quick to point out how much he has improved since he joined Ferrari, how he has often outpaced world champion Kimi Raikkonen this year and - apparently most persuasively - how he beat seven-time champion Michael Schumacher fair and square a couple of times when they were team-mates in 2006.
But it is debatable just how valid those arguments are.
Massa spun an embarrassing five times in the wet British Grand Prix
Massa has indeed improved since he joined Ferrari - but he remains inconsistent. The man who drove to sublime victories in Turkey and Bahrain this year is the same one who spun an embarrassing five times in the wet in the course of the British Grand Prix.
The comparison with Raikkonen is clouded by the Finn's mystifyingly plummeting form, which has left it far from clear whether the world champion remains the defining yardstick he has been in the past.
And despite Raikkonen's troubles, there have been races where what is considered the natural order of things has been restored and he has been clearly ahead of Massa.
But it is the Schumacher comparison that is most voiced in Massa's defence - and which simply does not stand up to analysis.
Massa won two races in 2006, in both of which the great German was still running at the finish. However, it is not true to say - as some do - that Massa was ever quicker than Schumacher - or even anywhere near him.
In Turkey, Massa qualified on pole, with Schumacher alongside him on the front row. But Schumacher was carrying eight laps' more fuel in his car, worth nearly a second in terms of lap-time deficit - and was still on course to beat Massa had he not made a mistake on his qualifying lap.
The heavier fuel load meant Schumacher would have easily beaten Massa in the race. But an awkwardly timed safety car meant Schumacher was queued behind Massa in the pits and the delay left him stuck behind Fernando Alonso's Renault, where he stayed for the rest of the race.
I thought we were going to have an off-camera fight
Massa's race engineer (above right)
The only other time Massa beat Schumacher was in Brazil, when Schumacher qualified in 10th position as a result of an engine failure and then suffered a puncture early in the race.
Of course, it is no shame to be outpaced by Schumacher in the same car but it is other aspects of Massa's F1 career that many of his critics cannot get past.
This is the guy who was outqualified by an average of 0.221 seconds by Nick Heidfeld in his debut season for Sauber in 2002 - and by about 0.5secs by Giancarlo Fisichella in his next F1 season, 2004.
Heidfeld and Fisichella are good drivers but they are not on the same level as someone like Schumacher, Alonso or Hamilton.
In Massa's defence, he was inexperienced when he came up against them but then so was Alonso when the Spaniard destroyed Jarno Trulli - who is arguably faster than both Heidfeld and Fisichella - at Renault in 2003.
Massa has driven to some impressive victories - but, excluding the ones he inherited in France and Belgium this year, all but one of his 10 wins have come when he has started from pole position, and the other was when he took the lead off the start-line.
He looks less comfortable beginning a race from anywhere else.
And he still leans far more heavily on his race engineer at Ferrari, Rob Smedley, than would be expected of a driver in contention for the world title.
Can Massa overhaul Hamilton, or will the Englishman hold on?
At Monaco this year, for example, Smedley needed to convince Massa that the Ferrari would go through the tricky first corner, Sainte Devote, much faster than he was driving it.
"It took a bit of persuasion, to be honest," revealed Smedley. "I thought we were going to have an off-camera fight but you have to have that relationship.
"It's so tight and it's so close that if the driver doesn't have someone backing him up who he can trust 100% - and that is the key point, there has to be 100% trust - then he is out on his own.
"The sport is so competitive, it's just really not possible to do everything on your own. Monte Carlo was one example you guys (the media) know about. There are many more.
"We have a lot of telemetry and you can see the car underneath him will do something that he sometimes doesn't trust in and it's just a question of pushing him or forcing him to do it."
Despite this need to hold Massa's hand, though, Smedley says he is convinced his man has what it takes to overhaul Hamilton.
"You've got a world champion in the making," he insisted. "He's doing everything right this year. The whole team is behind him and everyone is pushing as hard as we can.
Massa has benefited from Schumacher support at Ferrari
"He keeps delivering and he has to keep delivering if he wants to win the world championship. He knows that, we know that, and we just have to do it."
Should Massa succeed, there will be those who will shake their heads and say he is among F1's less deserving world champions.
But, for Brawn, that would be unfair. Ask him where Massa ranks in F1's current crop and he said: "If he's not at the top, he's very close.
"Felipe has got to show he can drive a team along, that when a team is not quite there he's one of the people who is standing behind it and making it work, in the way that obviously Michael was able to do at Ferrari.
"Even in the bad years Michael was a very strong element in helping to put it right.
"I guess those talents have got to be displayed for Felipe to stand up there with those sort of icons but there's no reason he can't.
"He has been maturing very well over the last couple of years. He has the speed and ability and the other side is coming along very well."