Nico Hulkenberg is happy with Carlos Sainz' contribution to Renault's development after assessing the Spaniard's performance in the final races of the 2017 season.
Although he never doubted his new team mate's talent, Hulkenberg wasn't sure if he would be facing a bitter rival or a valuable team member likely to spur Renault on.
Sainz took over from Jolyon Palmer late in the day, moving from Toro Rosso to Renault at the US Grand Prix.
Overall, Hulkenberg was satisfied with his maiden campaign with the French outfit.
"In terms of driving it was my best season so far," said the 30-year-old.
"As a driver I've never been better. The faster cars are more suited to me. I can drive at the limit and that's also more fun.
"The tyres have become much better. Everything went in the right direction," Hulkenberg told Auto Bild.
Based on Sainz's four races with Renault, the German cast a positive view on his input and next year's prospects.
"It was completely clear that Carlos would be closer. At the end of the day, we are all only cooking with water," added Hulkenberg.
"Sainz is talented and fast. We are only at the beginning of our team relationship, but Carlos is important for the development of the team."