Matzek departed Milwaukee and will undergo an MRI exam on Wednesday in Atlanta. The 2021 postseason hero said he has been experiencing pain for the past couple weeks.
"It was probably two weeks or three weeks (ago) that my shoulder started feeling uncomfortable," Matzek told MLB.com. "I think I was just compensating for the lack of mobility in my back. I felt good trying to get through the back (injury). I think it just spiraled into another thing."
Matzek, 31, has struggled with a 5.06 ERA in 13 relief appearances this season. He has experienced major control issues, walking nine in just 10 2/3 innings.