Sauber is eyeing Ferrari Driver Academy member Charles Leclerc as a its potential reserve driver for the 2017 season.
French hopeful and GP3 champion Leclerc enjoyed a bout of F1 experience last season, having taken part in four practice sessions with Haas last year.
While Antonio Giovinazzi was drafted in last week by Sauber to replace the then still-recovering Pascal Wehrlein, the Italian has already been named as Ferrari's back-up man.
Wehrlein was back in action this morning with Sauber before Marcus Ericsson took over after the lunch break.
Leclerc will be graduating to GP2 this year, tackling the competitive series with prime Italian outfit Prema.
GALLERY: F1 drivers' wives and girlfriends
Keep up to date with all the F1 news via Facebook and Twitter
