Brentz will enter the starting nine in place of J.D. Martinez, who was scratched after experiencing back tightness. The 30-year-old Brentz missed some time last week due to an illness, but his availability Wednesday suggests he's back to full strength. As a non-roster invitee, Brentz is a long shot to break camp with the big club and is expected to open the 2019 campaign at Triple-A Pawtucket.

Brentz is the latest Red Sox player to come down sick, joining Steve Pearce and Brian Johnson. He should be considered day-to-day.

The reason for Brentz's scratch is not yet clear. Tate Matheny will take his place in the lineup, batting sixth and playing left field.

The 30-year-old Brentz will rejoin the organization he started with back in 2010. The Red Sox eventually cut ties with Brentz -- the victim of a roster crunch -- after the 2017 season. There's some power potential, as he's whacked 46 home runs with an .877 OPS over 175 games at the Triple-A level the last two seasons. The deal also includes opt-out language, allowing Brentz to bolt if a better opportunity comes along. He's not expected to challenge for a spot in Boston, so if he remains in the organization, it'll be as an outfielder at Triple-A Pawtucket.