Gunther Steiner feels Romain Grosjean did not get enough credit through his Formula 1 career, saying he was "one of the best ones out there" on a good day.
Haas announced in October that it would not be retaining Grosjean for the 2021 season, ending the Frenchman's five-year stint with the American team as it ushered in an all-new line-up.
Grosjean made his final start for Haas at the Bahrain Grand Prix, where he escaped a fiery accident on the opening lap before being ruled out of the final two races of the season due to the injuries sustained to his hands.
He has shown an interest in returning to racing in IndyCar, Formula E, or the World Endurance Championship in the future, but also wants a private F1 test to mark his final act in the series.
Despite gaining a reputation at points for on-track incidents and mistakes, Grosjean ended his time in F1 with 10 podium finishes to his name, and recorded the best result in Haas's short history with fourth at the Red Bull Ring in 2018.
Asked if he felt Grosjean sometimes failed to get the credit he deserved, Haas team boss Steiner told Autosport: "Yes. He was for sure very fast.
"On a good day, Romain was one of the best ones out there.
"But he sometimes pushed and tried too hard. Then you see those errors. He just went over the limit and then the errors come."
Grosjean spent four of his five seasons with Haas racing alongside Kevin Magnussen, who agreed with Steiner's summation.
"There's been some mistakes that he's made that have been big, say the Baku one [in 2018], where he crashed under the safety car," Magnussen told Autosport.
"That got so much attention, but if you look at what position he was in when he crashed, that was unbelievable. I think it was fourth or something, in the Haas!
"Nobody ever talks about that. Had he not crashed under the safety car, he would have had an unbelievable result in that race.
"It takes away from what an absolutely amazing driver that he is. I think over the last years, him being in an uncompetitive car as well has just meant it's been hard for him to really show.
"But then people have forgotten what he did back in 2012, 2013, those years where he was on the podium so many times.. It's only down to bad luck he didn't win a race on quite a few occasions.
"That's just how the world works at the moment. Certainly from the inside, being his team-mate, I admire him for the talent he is."
Grosjean quit Lotus at the end of 2015 to join Haas for its debut season in F1, helping build the start-up squad into a regular midfield contender.
Steiner said that Grosjean was "brave" in his decision to join Haas, but that the team also delivered on everything it promised him.
"We were as prepared as I promised him when we spoke about it," Steiner said.
"The difficult bit at that time was there were a few new teams which didn't deliver, and he knew this could happen, but I explained to him how we are doing it differently. He believed in it and I think we delivered.
"Obviously the  season and  were difficult for us, but you can have that in any race team. That had nothing to do with the team being new anymore, that was we got something wrong last year and this year with the pandemic we suffered more than anybody else.
"He was brave to do it and it didn't work out badly for him."