The term slot receiver conjures a specific image in my mind. It's of Wes Welker. The 2007 Patriots owe much of their historic offensive outburst to Tom Brady and Randy Moss, perhaps the best to ever play their respective positions. But the 5-foot-9, 185-pound Welker enjoyed his own breakout with the team, catching a league-leading 112 passes and cracking the top 10 wide receivers in PPR formats. Welker went undrafted out of Texas Tech in 2003 thanks to the physical tools one would expect of a player of his stature. His skills were short-area quickness and guile, things more difficult to measure than traditional combine tests such as the 40-yard dash.