Coach John Harbaugh said Walker's lack of playing time in a preseason win over Atlanta on Saturday was related to a rib injury, Jeff Zrebiec of The Athletic reports.
The rookie fourth-round pick has only one target and no receptions through two preseason games and doesn't seem to have gotten any snaps before halftime. This perhaps mitigates concern about Walker's progress, but it does seem he's headed for a lower spot on the depth chart to start the season, likely behind Zay Flowers, Rashod Bateman and Nelson Agholor at the very least.