Nico Rosberg believes Carlos Sainz is as good as Max Verstappen but unable to show it in an inferior car to the Dutchman.
Verstappen and Sainz were rookie team-mates at Toro Rosso in 2015 and again at the start of this year before Verstappen was promoted to Red Bull in place of Daniil Kvyat after four races of the season. Sainz has been retained at Toro Rosso for another year after links with Ferrari and Renault, and Rosberg believes the two are closely matched.
"He is the Spanish hope, is very good, very strong, but the situation is difficult because the good car has been given to Verstappen," Rosberg told Spanish publication AS.
"But as I say Carlos is also very strong and against Verstappen did very well. His behavior was very similar ... they are as good as one another and I am convinced that he will be one of the good drivers, one of the important ones in the future."
Sainz pointed to a number of reliability issues in 2015 as he scored 18 points compared to 49 for team-mate Verstappen at Toro Rosso. The Spaniard was again trailing by nine points after the opening four rounds this year before the change in driver line-up, with Verstappen going on to secure one victory and five further podiums since that point.
So far, Sainz boasts a best result of sixth place this season - scored in Barcelona - as Toro Rosso's competitiveness has trailed off due to its use of a 2015-specification Ferrari power unit.
Scene at the 2016 Japanese Grand Prix
Japanese Grand Prix - Quotes of the week
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