Toro Rosso boss Franz Tost says Jean-Eric Vergne needs a big result in Formula 1 to validate the progress he has made this season.
Vergne was overlooked in favour of 2013 team-mate Daniel Ricciardo for a graduation to Red Bull for this season, and has spent this campaign facing up to the new challenge of rookie sensation Daniil Kvyat at Toro Rosso.
Tost conceded reliability problems had denied both his drivers several opportunities to score big points - a pair of eighths stand as Vergne's best results of 2014 so far - but reckons this is even more crucial for Vergne, who is now in his third season in F1 with STR.
"He made a lot of progress during the winter months so he is much more [mentally] stable this year," Tost told AUTOSPORT.
"He is doing a good job. Unfortunately he has had a lot of reliability issues with his car, but from the driving point of view he is fast, skilled, and I just hope he gets a really good result.
"Monaco [where Vergne ran as high as sixth before an unsafe release and ignition problems] would have been the kick to give him self-confidence to score a lot of points, and then everything becomes much easier.
"You need the results because this is the confirmation. Otherwise it's just talk, philosophy."
BOUNCING BACK FROM 'DIFFICULT MOMENT'
Vergne says he has worked hard to recover from the disappointment of losing out on the Red Bull drive to Ricciardo, who has gone on to record his first two wins in F1 across the first 11 races of 2014.
"Last year was obviously a difficult moment," Vergne told AUTOSPORT.
"I think halfway through last year Daniel was definitely better than me in qualifying, but I was always catching up in the races.
"I understood that I needed the winter break to understand the decision and to get over it, and still be grateful that I am able to keep going with a team that has a lot of potential.
"I'm not the sort of driver to say 'we could've done this, or this,' but I have to say I have had a lot of bad luck this year and there have been many races I was unable to finish where I could have been in the points.
"It's a bit of a shame because we need the results, and when you don't get the results, it doesn't matter how good you could have done, as people forget the week after.
"The positive is that I have done a good job so far and the team has done a good job so far. We just need to keep going and the results will come."