Johnson, also a standout returner, has compiled 757 all-purpose yards this season. Johnson was suspended for Texas' victory over Texas Tech on Thanksgiving after breaking undisclosed team rules, as well.
Estelle has started eight games at right tackle, and has been a key piece on the Texas offensive line.
Overstreet, a reserve running back, has 102 rushing yards and two touchdowns.
The Longhorns (8-4) face Oregon (10-2) on Dec. 30.