Yes, the first few rows of some lower level sections can have partially obstructed views because of the players on the sideline. The seats are elevated slightly off the ground so the opposite side of the field will still be clear but the players can still block some of the field. Part of the near side of the field may be obstructed for about the first 5-10 rows of some of these lower level sections near midfield.
Sections C, D, E, Q, R, and S are most susceptible to potential obstructions because they are closest to the bench areas of each team. The front rows of all sideline sections may be obstructed occasionally, depending on where the action is occurring on the field, but it happens most frequently in these sections.