There are a total of 21 seats in Section 207 Row 3 at Petco Park. As you face the field from the section, Seat 1 will be on the aisle at the left side of the row, while Seat 21 is on the aisle at the right side of the row.

Section 207 Row 3 Seating Layout at Petco Park
Seat 1 will be on the aisle at the left side of Section 207 Row 3, while Seat 21 is on the aisle at the right