Mercedes have confirmed Nico Rosberg will test at Barcelona on Friday as "scheduled".
With an unwell Lewis Hamilton pulling out of Thursday's running, many questioned why test driver Pascal Wehrlein was called up instead of Rosberg.
It emerged that Rosberg was suffering from a trapped nerve in his neck.
Having received treatment, the German, who finished runner-up to Hamilton in last year's Championship, will take place his place in the W06 on Friday morning.
Mercedes tweeted on Friday morning that he would be "at the wheel today, as scheduled".