Romain Grosjean's positive report on Esteban Gutierrez played a part in Haas's decision to recruit the Mexican for its Formula 1 debut this season, according to team principal Gunter Steiner.
Grosjean was confirmed as a Haas driver in September last year after the Frenchman opted to end his time with Lotus.
After recruiting Grosjean, Steiner and eponymous Haas owner Gene asked him for his thoughts on Gutierrez, who spent last year with Ferrari as test and reserve driver following two seasons with Sauber.
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"When we picked Romain we spoke with him about Esteban," Steiner confirmed to Autosport.
"If he had said he didn't get on with him or something, or if there was no respect more than anything else, it would have been hard [to then sign him].
"Obviously Esteban is a good driver, but we didn't know him then as well as Romain, who had raced against him.
"Romain knows his technique as a driver, and knows more about him as a guy, whether he is stable or unstable, and he was very positive about him."
Steiner has no doubt Grosjean and Gutierrez will form a solid, reliable pairing that will work in harmony together.
"What we think is they will get on pretty well because they are both intelligent guys, and not just as race car drivers, but as human beings in general," added Steiner.
"They've both had a good education, they are at a good level, and I think they will get on - or at least I hope so."