Nick Heidfeld and Robert Kubica spent four seasons racing alongside each other at BMW Sauber over a decade ago, but the German wasn't always happy with his teammate's behaviour.
Speaking in Formula1.com's latest Beyond the Grid podcast, Heidfeld praised Kubica for his "amazing" comeback last season in F1, even if results were few and far between for the Pole, and remembered the latter as the most "complete" driver he ever had as a teammate.
"He is a hero to come back after that accident, even if his performance was not what most of us would have liked, including himself, to come back after that, not only physically but also mentally, is amazing," said Heidfeld.
"He was the team mate I had the longest in Formula 1. I would say that he was the most complete of all the team mates I had.
"He was not as quick as Kimi [Raikkonen] was in the race. He was not as quick as [Mark] Webber was in qualifying.
"Obviously, that’s my personal view. But overall, as a whole package, he was really up there."
However, during their time together at BMW Sauber between 2006 and 2009, Heidfeld took exception to Kubica's depiction to the press of life within the Swiss-German outfit.
"What I didn’t like about him, or maybe what was also for himself something not really helpful, is that he most of the time thought that the team was benefiting me over him because it was a German team, with BMW, and I was a German driver," he recalled.
"I didn’t like it because he did put that out in the press quite often and I think it was simply not true, always saying the team prefers me over him and I get better whatever. That was not true."
Heidfeld conquered 13 podiums during his 12-year career in F1, eight of which were achieved with BMW Sauber, but the German never won, a shortfall that constitutes a record in F1's history books.
During the same four-year period at BMW Sauber, Kubica snatched nine top-3 finishes, including his victory at the Canadian Grand Prix in Montreal in 2008, the Polish driver's his single Grand Prix win.
Both Heidfeld and Kubica moved on from BMW Sauber at the end of 2009 when the German manufacturer pulled the plug on its involvement in F1.
In hindsight, Heidfeld believes BMW threw in the towel too early.
"I think one of the biggest facts was that they just pulled out too early in my view as a racing driver," he said.
"In the view of the team and BMW as a whole, looking at the financial crisis we had back then, it probably was the right decision, I don’t know. But if you look at their results, I think they did really really well.
"Coming with a relatively small team, with Sauber, moving up the ladder, it is normal that sometimes that there is a step back. And then they just pulled a plug too early, I think."
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