A test plug for insertion into and plugging of an open end of an elbow pipe is provided. The test plug includes a resilient sealing element and set of gripper segments carried on a shaft. The set of gripper segments are movable relative to the shaft between pipe-gripping and pipe-non-gripping positions such that, when the test plug is placed in sealing and gripping engagement relative to an inner diameter wall of an elbow pipe, the set of gripper segments are positioned in eccentric relation to at least one of the sealing element and the shaft