relief pitcher

(n) A vibrator or other sex toy a woman may resort to if her partner (the "starter") can't finish the job.

For males engaging in a sexual act with a woman: An alternate source of stimulation used when the currently enacted source of stimulation becomes tiresome to the male giver. The act of switching from vaginal sex to digital stimulation would be considered "bringing in the relief pitcher." Often used to conceal physical weakness and to the female recipient is seen merely as "switching it up." Can help maintain pleasure levels. Keeps manhood in check.