To start the campaign, the Silver Arrows had an uncharacteristically poor car and even after upgrades throught the year, George Russell scored their one and only win for the season in Sao Paulo - a scenario that many would have thought impossible at based on their previous dominance of the sport.
Mercedes finished third in the Constructors' Championship after having won the previous eight in a row and Lewis Hamilton finished a career-low sixth in the Drivers' Championship
"Extremely tough, because we have given him a tool that wasn't capable of winning," Wolff said on Formula 1's Beyond the Grid podcast. "On top of that, the drivers had a car that was unpredictable, unstable, good at times, not good at others - not really something you can work with and develop.
"But as a personality, how he has gone through the season is really admirable. There were times when the team felt down because of the non-performance and this is where he picked the people up and motivated them, and that is truly management and personality traits that I have not seen with a professional sportsman before.
"Obviously there's his involvement in developing the car, and his presence in the factory, but I think on the race weekends he has become such a senior figure," Wolff added.
"[He's] maybe a little bit like Michael [Schumacher] was back in the day, or I think about Tom Brady in [American] football teams, that you become more than just a player or just a driver. You are emotionally part of the team, and he definitely is.
"He's not, like we called them in the past, a contractor - drivers come, get paid and they leave for the next better occasion. He's been with the team now ten years [and] he's a team member."