Sauber is set to make a "big step forward" in 2018 team principal Fred Vasseur has claimed after a number of major problems left the Swiss team bottom of the constructors' championship last year.

The former Renault boss replaced Monisha Kaltenborn at the helm of the Hinwil-based outfit midway through last season and has been tasked with leading the rebuilding of an operation which almost collapsed due to financial problems just two years ago.

Under the ownership of Longbow Finance for the last 18 months, a company with ties to driver Marcus Ericsson, Sauber is now starting to get back on its feet, but, as Vasseur explained, the impact on the team's competitiveness was long-lasting.  

"The 2017 car was ready very late. It was a new project and if you are six months late, it only adds to a difficult situation and it's very difficult to catch up," he told French publication Auto Hebdo.

"The decision to use the 2016 Ferrari engine last year also did not help," Vasseur added.

For this year, however, the outlook is much brighter, a whole new car is being designed under the guise of well-respected technical director Jorg Zander and Sauber has in man ways relaunched their relationship with Ferrari, taking on junior driver Charles Leclerc and welcoming Alfa Romeo back to F1 as title sponsor.

"Yes, there are many expectations and I think we have made some strong choices," the team boss claimed. "Above all with the engine, having the 2018 Ferrari engine will mean a big step forward for us and we have started with a new philosophy for the car."