FFImpulse - Final Fantasy X

Blitzball- The Blitzball Playing Field

A circular mini map is displayed on the right side of the screen. The map shows the positions of both teams. Each team has six members: Left Forward (LF), Right Forward (RF), Midfielder (MF), Left Defense (LD), Right Defense (RD), and Goalie (GL). Your players are marked by green triangles, while oppsoing players appear as red triangles.
The player with the ball is highlighted with a colored circle around his/her triangle. His or her attributes are shown in the upper-right hand corner of the screen.

Am I invisible?

Since the field of vision inside the sphere poll is somewhat limited, try moving your players while watching the mini map instead of the actual field. This should help you control your players a little bit easier.