Tost critical of Sainz's will to leave Toro Rosso

Toro Rosso boss Franz Tost believes Carlos Sainz owes an allegiance to Red Bull and should consider himself lucky to be in F1.

As a Toro Rosso-Honda partnership looms following a probable engine supply deal between McLaren and Renault, Sainz could join the French manufacturer's works team as part of a compensation package required by the latter in order to end its contract with Red Bull's junior outfit.

Regardless of the ongoing complex negotiations and their ultimate outcome, Tost would disapprove of Sainz's departure.

"Carlos has a contract with Red Bull which financed his career," the Austrian manager told France's Auto-Hebdo.

Sainz could be on the move, but not to Renault

"And now that he has reached maturity, we should let him go? Red Bull isn't in the business of forming drivers for other teams.

"What if something happens to one of Red Bull Racing's drivers? This is precisely why Red Bull has two teams in F1."

Tost believes the energy drink company's heavy investment in young talent warrants a return, something obviously lost on Sainz says the Austrian.

"They've invested a lot of money and I don't accept a driver waxing on about how "I want to join another team".

"He should be happy to be n Formula 1, especially as the Toro Rosso is a good car..."

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Phillip van Osten

Motor racing was a backdrop from the outset in Phillip van Osten's life. Born in Southern California, Phillip grew up with the sights and sounds of fast cars thanks to his father, Dick van Osten, an editor and writer for Auto Speed and Sport and Motor Trend. Phillip's passion for racing grew even more when his family moved to Europe and he became acquainted with the extraordinary world of Grand Prix racing. He was an early contributor to the monthly French F1i Magazine, often providing a historic or business perspective on Formula 1's affairs. In 2012, he co-authored along with fellow journalist Pierre Van Vliet the English-language adaptation of a limited edition book devoted to the great Belgian driver Jacky Ickx. He also authored "The American Legacy in Formula 1", a book which recounts the trials and tribulations of American drivers in Grand Prix racing. Phillip is also a commentator for Belgian broadcaster Be.TV for the US Indycar series.