Verstappen, 17, feels that Vergne's experience will benefit the Italian squad and also be critical for his own development during his maiden Formula One season.
"It is important to keep Jean-Eric, I think it will be a big help," Verstappen said in Austin, where he substituted for Vergne during FP1. “He has experience with the tyres already so he can help me a lot with that. But I think also in general for the team it is a big help.”
Vergne formally lost his Toro Rosso seat in August when the team announced his current team mate Daniil Kvyat and Verstappen as their 2015 line-up. However, with Kvyat subsequently promoted to Red Bull to replace Sebastian Vettel, the Frenchman could in theory retain his drive.
"For sure times will be closer [between two rookie drivers] - if you have an experienced driver maybe the times will sometimes be bigger, but you can learn from that,” added Verstappen.
"Where I'm at with the tyres, if you have someone like Jean-Eric for sure they will help - not only for one race but I think the whole season. I think it is a win-win situation for me and the team."
Toro Rosso team principal Franz Tost revealed in Austin that Vergne is one of four drivers in contention for the 2015 seat. The other three drivers - 2014 Formula Renault 3.5 champion Carlos Sainz and runner-up Pierre Gasly, and 2014 GP3 champion elect Alex Lynn - would all be F1 rookies.