In a right triangle, one angle is always \(90^\circ\). The sum of the angles in any triangle is \(180^\circ\). If one angle is \(58^\circ\), the third angle can be calculated as follows:
\[ \text{Third angle} = 180^\circ - 90^\circ - 58^\circ \] \[ \text{Third angle} = 90^\circ - 58^\circ \] \[ \text{Third angle} = 32^\circ \]
So, the measure of the third angle is \(32^\circ\).