Who was the quarterback Tom Brady replaced as New England's starter?

Tom Brady replaced Drew Bledsoe as the New England Patriots’ starting quarterback in 2001.

Bledsoe had been New England’s established starter and signed a 10-year contract extension before the season. In the Patriots’ second game, on September 23, 2001, New York Jets linebacker Mo Lewis hit Bledsoe, causing a serious chest injury. Brady, then a second-year quarterback and former sixth-round draft pick, entered the game.

Brady started the following week while Bledsoe recovered. Even after Bledsoe was medically cleared to return, Patriots coach Bill Belichick kept Brady as the starter because the team was winning and Brady had performed well. Bledsoe later returned in the AFC Championship Game after Brady was injured and helped the Patriots reach the Super Bowl.

The Patriots defeated the St. Louis Rams in Super Bowl XXXVI, launching Brady’s historic career. Bledsoe’s injury and Brady’s promotion became one of the defining turning points in NFL history.