Guendling attended St. Viator High School, where he was a three-year starter at linebacker.
As a junior, he had 20 tackles (13 solo), helping the team beat Michigan State University and end a string off 44 consecutive road loses.
As a senior, he had 7 solo tackles (3 for loss), 2 sacks and 4 pass breakups in a 10-8 win against Indiana University.
[1] Guendling was selected by the San Diego Chargers in the second round (33rd overall) of the 1984 NFL draft.
[4] He wasn't able to regain his previous form after his knee injury and was waived on August 20.