Antonio Giovinazzi will replace Pascal Wehrlein for the second race in a row and drive for Sauber in this week's Chinese Grand Prix.
Wehrlein is battling to regain fitness following a crash in January's Race of Champions event which meant he missed most of pre-season training and testing.
Giovinazzi, 23, finished 12th on his grand prix debut in Melbourne 10 days ago, having had just two days of pre-season testing with the Sauber team.
"For me the most important is that I can train intensively to ensure a 100 percent performance from my side as soon as possible," Wehrlein said in a statement posted late Monday on the Sauber team website.
The 22-year-old German is hoping to be able to return at next week's Bahrain Grand Prix but admitted he might have to wait until the Russian Grand Prix in Sochi, which is three weeks away.
"Hopefully this can be in Bahrain but, if not, then we will take the time it needs until Russia to make sure I am completely ready," said Wehrlein.