Bernie Ecclestone says the only way to truly know who is the better driver out of Lewis Hamilton and Max Verstappen would be for the pair to race on the same team.
While a Red Bull move for Hamilton is unlikely, Mercedes have twice sought Verstappen's signature, once before he signed with Red Bull in 2015 and then again in 2017, before he signed a lucrative extension with his employers.
Verstappen has been unable to challenge Hamilton's dominance of F1 since signing for Red Bull as they have struggled to match Mercedes consistently, although it is hoped that 2020 may bring them into direct combat more.
With Hamilton having previously teamed with world champions in the form of Fernando Alonso and Jenson Button, as well as Nico Rosberg, who won the title in his final F1 season in 2016, Ecclestone says Verstappen and Hamilton can only be properly measured against each other if given identical machinery.
Ecclestone told Auto Motor und Sport: "These are two different drivers, two completely different types - and they also win their races in different ways.
"That's why the choice is hard for me. We could really compare the two in the same car. I wish to see that."
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