'Jeopardy' champ Ken Jennings recalls shock of seeing Alex Trebek pantless

'Jeopardy' champ Ken Jennings recalls shock of seeing Alex Trebek pantless

The late host tried to diffuse the tension during the high-stakes Ultimate Tournament of Champions in 2005.Bryan Bedder/Getty; Eric McCandless via Getty Ken Jennings; Alex TrebekThey say imagining someone in their underwear will make you less nervous. For contestants on Jeopardy's Ultimate Tournament of Champions in 2005, no imagining was needed.Former champ-turned-host Ken Jennings took a trip down memory lane recently, reminiscing about his ol…