Former Vikings DL Christian Ballard is suing the NFLPA for allegedly withholding information from its players about the risk of head injuries.

A fourth-round pick in the 2011 draft, Ballard is coincidentally representing the players association in a grievance concerning roughly $240,000 in 2013 base salary he collected, but the Vikings are trying to recoup. Ballard essentially quit the team last September. His career appears over at age 25.

Vikings placed DL Christian Ballard on the active/left squad list.

Ballard exited camp citing "personal reasons." A 2011 fourth-round pick, Ballard has been a disappointment through two seasons and is on the bubble. No matter the cause, missing camp reps will hurt Ballard's chances of making the 53.

Vikings DL Christian Ballard's roster spot is in danger after the team drafted Sharrif Floyd and Everett Dawkins while signing Lawrence Jackson.

Barring injuries ahead of him on the depth chart, 2011 fourth-rounder Ballard may be on the outside looking in after what beat writer Tom Pelissero describes as a "pedestrian" first two seasons in the league. Ballard is a 'tweener tackle/end and has managed one sack amongst 29 tackles through 32 appearances.

Vikings GM Rick Spielman expects 2011 fourth-round pick Christian Ballard to play a bigger role in 2012.

Ballard, who just turned 23, flashed rare versatility and some run-defending prowess in a part-time role as a rookie. "He's going to be a heck of a player and continue to make a jump," Spielman said. Ballard can play four positions on the line. He projects as the Vikings' No. 3 defensive tackle behind Kevin Williams and Letroy Guion. Ballard could even push Guion to start.