Worcestershire have made two changes for the home LV = County Championship match with Hampshire at New Road.
Tom Kohler-Cadmore, who recently scored 150 for the Seconds against Yorkshire, replaced Alex Gidman and Brett D'Oliveira came in for Ed Barnard.
Gidman is still recovering from concussion after being struck on the head by a Ben Hilfenhaus bouncer at Trent Bridge last week.
Director of Cricket Steve Rhodes said: "Alex has not quite recovered from the concussion that he got at Trent Bridge. You have to be careful with such things.
"If you are showing signs of it, and you get hit again, there are problems. We want to look after our players.
"They are really important to us and to not put him in that firing line, if he is not right, is the right thing to do, for the welfare of the player."
D'Oliveira will be making his first Championship appearance of the season as Worcestershire opt to play two spinners. He has impressed in the Second Eleven Championship with bat and ball.
D'Oliveira had previously made three Championship appearances in 2012 and one in 2014.
Rhodes said: "He looks as if he is an 18-year-old, but he is not an 18-year-old anymore.
"He shows now in the second team what a vastly experienced cricketer he is in that format.
"As he shows in the T20s as well, he is a ready made first team player now."