Here's the breakdown of how these two training camp injuries shake out for McCarthy's Steelers:
Michael Pittman Jr. (WR) — Leg injury, not serious
This is a minor setback. Per the team, Pittman walked off during a Saturday Night Lights drill, spent just a few minutes with trainers, and returned to the sideline. He'll likely be held out of preseason games as a precaution. Since McCarthy's offense runs heavy 11 personnel (80%+ of dropbacks) and is built on timing and short routes (76% of Rodgers' attempts last year were under 10 air yards), Pittman's role as the WR2 / short-area complement to DK Metcalf is well-defined and won't change. His absence in camp just means more reps for Germie Bernard and the depth receivers, and potentially more work for the RB committee (Rico Dowdle, Jaylen Warren) in the passing game until he's back. (from the Michael Pittman Jr. page, Mike McCarthy page)
Jaquan Brisker (S) — Unspecified injury, not serious
Brisker is a defensive player, so this doesn't affect McCarthy's offense at all. On defense, though, Brisker was a key piece in DC Patrick Graham's plan to unlock Jalen Ramsey as a "chess piece" — he enabled more two-high safety looks that let Ramsey play closer to the line. His absence likely pushes DeShon Elliott into more snaps, and may limit how creative Graham can get with Ramsey's alignment early in the season. (from the Jaquan Brisker page, Jalen Ramsey page)
Bottom line: Both injuries are being described as precautionary, not serious. The offense's identity — short passing, 11 personnel, West Coast timing — stays the same regardless.