Ex-Formula 1 driver Johnny Herbert says Stoffel Vandoorne's fate is the perfect example of how a career in F1 is "not a given" for rising stars such as Lando Norris.
Vandoorne has a sparkling junior single-seater CV, having won the Formula Renault Eurocup in 2012, then finished second in Formula Renault 3.5 and GP2 in 2013 and '14 respectively.
He dominantly won the 2015 GP2 title before a race-winning spell in Super Formula the following year, and began his first full F1 season with McLaren in '17 having scored a point on his debut as Fernando Alonso's stand-in in Bahrain the previous year.
But two lacklustre seasons where Vandoorne has struggled to impress alongside Alonso means he is being replaced by F2 title contender Norris and does not currently have a 2019 F1 seat.
Three-time grand prix winner Herbert said Norris and fellow Briton's George Russell's F2 performances should be a sign both would thrive in F1 but that this could not be taken for granted.
"I hope it's a sign, as young as they are, that they will be able to jump into a Formula 1 seat and do the job," said Herbert.
"But you always have Stoffel Vandoorne's story.
"Take Lando, you have to be very aware that it's not a given that it's an easy scenario and everything is going to work out for you.
"Vandoorne had a brilliant career through the single-seater categories and gets to F1 and sadly it hasn't happened for him.
"You have to capitalise on the chance.
"They are young, yes, but it doesn't matter.
"If you don't do the job, you'll be out, and it's damn hard, unless you have a load of money in your pocket, to come back in again.
"You've got to grab it by the horns and use the situation you have to your advantage."
While Norris has his F1 seat for next year confirmed, F2 points leader Russell's situation is complicated.
The Mercedes junior has carried out testing work for Racing Point Force India, but with Lance Stroll looking certain to join Sergio Perez at the team, that seat is off the table for Russell.
Russell, who leads Norris by 22 points with two F2 events remaining, also appears to have fallen down the pecking order at Williams.
The team recently decided against strengthening its ties with Mercedes by adding its gearboxes to the engine deal it already has for 2019.
"If George goes on to win the championship, and personally I think he will, he should get an F1 drive," added Herbert, .
"It's good getting this experience from F2, in this tense battle that they have been in since race one.
"Hopefully they will be able to use that to their advantage in F1.
"That's where the hard work really starts, it's getting that momentum and carrying that through.
"The confidence that gives you is so, so powerful."