The duo will join hundreds of players in the XFL's first post-revival draft on October 15 and 16.
The letter criticized the player's dreadlocks, which the author, who signed his name as Dave Petersen, called "disgusting" and "certainly not attractive."
Clifford passed for 264 yards and scored four total touchdowns in Penn State's 35-7 victory over Purdue on Saturday afternoon.
The Nittany Lions dropped three spots from their previous ranking of No. 5, which they held for two consecutive weeks.
From Michael Scott to Randy Jackson to the quintessential Michigan fan meme, only GIFs could properly summarize Wolverine fans' reactions to a primetime White Out.
A White Out under the lights, just like God intended.