Leclerc outperformed the Swede throughout the year, and scored a majority of Sauber's points. Towards the end of the year, the team took the decision to replace Ericsson with Ferrari junior Antonio Giovinazzi for the 2019 season.
But Vasseur has commended the now third driver for Sauber, stating that he vastly improved for the 2018 season: “I think (Leclerc) did a very good job, and he did a very good job also because Marcus was improving,” Vasseur said to RACER.
“If you consider Marcus compared to (2017) I think he did a huge step forward. When he first hit the track in Melbourne he was six kilos lighter than the previous year and from the beginning he made a step forward from then.
“Even in the last part of the season, he was consistently at the same lap time as Charles. He was in front of Charles in Sao Paulo, just behind in Austin, and it was very helpful for Charles as well to have someone as a reference like Marcus.
“Marcus also has the advantage of very good technical feedback and he helped us a lot at some stages of the season to take decisions on the technical side. When you come to F1 from F2 it’s not easy to have a reference on the performance.”
Bahrain International Circuit - Winter testing