HOUSTON -- A white Texas school superintendent who posted online that "You can't count on a black quarterback," in reference to Houston Texans quarterback Deshaun Watson, has resigned.

In a letter Saturday to the Onalaska Independent School District board, Lynn Redden said his comment posted earlier in the week on the Houston Chronicle's Facebook page was "wrong and inappropriate."

He also apologized to Watson, who is black, and pointed out that the quarterback could have criticized him for his comment but instead "chose peace and positivity."

Redden had criticized Watson for letting the clock run down before completing a pass in a 20-17 loss to the Tennessee Titans on Sunday.

Redden's comment prompted the school board to convene a special meeting Saturday.