Germany - Formula 1 legend Gerhard Berger hopes Fernando Alonso's decision to do the Indy 500 in May is the start of a new trend.
When referring to when drivers would routinely combine their F1 duties with races into other categories, Berger said: "It's like the old days.
"We must finally break these formalities.
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He added: "In 1985 I drove for Arrows in Adelaide and the day before did a national touring car race for Bob Jane.
“It was still possible in those days and everyone had their fun."
Berger is now the boss of the German touring car series DTM, and he hopes Alonso's move to Indy is the start of a new trend.
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He added: "I'm sure Vettel would like to do DTM races if he could," said the Austrian.
"Drivers today have much more spare time than we used to, as there is hardly any testing."