The teams will remain at the Circuit de Catalunya for two days of testing following today's Spanish Grand Prix, with running taking place on Tuesday and Wednesday. With Wehrlein having tested for Force India when it was running last year's car during pre-season, he will get his first taste of the team's 2015 car on the opening day.
Yelloly will then take over on Wednesday, making his first appearance in an F1 car. The British driver is racing in GP2 this season for Hilmer Motorsport, with Force India confirming his test debut via Twitter.
"On Day 1, Pascalwill get his first run in the VJM08, while on Day 2 it will be 's turn to get some mileage!" Force India tweeted. "Nick has been doing simulator work for us this season and his presence in the car will provide us with valuable feedback."
Force India has already announced it will introduce a B-spec car at the in-season test in Austria, which takes place in June. Teams are required to run a rookie on at least two of the four days of in-season testing this year.
Click here for Saturday's gallery from the Spanish Grand Prix