McCann, 35, exited Tuesday night’s game against the Marlins after three innings due to knee discomfort. It’s not clear if any one particular event sparked the discomfort, but knee issues have slowed McCann in recent years. He underwent arthroscopic right knee surgery last year.
Across 274 plate appearances this season, McCann has hit a respectable .264/.336/.423 with 10 home runs and 39 RBI, splitting catching duties behind the plate with Tyler Flowers.
Jackson, 23, is the Braves’ No. 25 prospect according to MLB Pipeline. He debuted and had a brief cup of coffee in early April, going hitless in 11 plate appearances. Jackson’s performance for Gwinnett has been much better, batting .224/.311/.510 with 25 home runs and 57 RBI over 328 PA.