The weakside linebacker (WLB), or the "Will" in 4–3 defense, sometimes called the backside linebacker, or "Buck", as well as other names like Jack or Bandit, must be the fastest of the three, because he is often the one called into pass coverage. He is also usually chasing the play from the backside, so the ability to maneuver through traffic is a necessity for the Will. The Will usually aligns off the line of scrimmage at the same depth as Mike. Because of his position on the weakside, the Will does not often have to face large interior linemen one on one unless one is pulling. In coverage, the Will often covers the back that attacks his side of the field first in man coverage, while covering the weak flat in Texas Loop or hooks/curl areas in zone coverage. The weakside linebacker is also commonly known as the right outside linebacker (ROLB).