In Steve Spurrier's first season as coach, the Redskins had been all about offense in their first three preseason games. On Saturday, it was the defense that took center stage.
The Redskins forced six turnovers, including getting a pair of touchdowns from their defense.
Defensive end Gregory Scott recovered a fumble by Tampa Bay quarterback Rob Johnson on his own 34 with 6:19 remaining in the third quarter and rambled 66 yards for a touchdown to give the Redskins a 23-10 advantage.
Linebacker Donte Curry intercepted third-string quarterback Shawn King and scampered into the end zone from 20 yards with 2:31 left in the fourth, making it 40-10.
Matthews completed 8-of-15 passes for 97 yards with one touchdown and an interception.
First-round pick Patrick Ramsey replaced Matthews in the second half and went 10-of-20 for 117 yards, including a 12-yard touchdown pass to former Buc Jacquez Green in the fourth quarter.
Kevin Lockett had five catches for 71 yards for the Redskins, who have won their four exhibition games while averaging an impressive 37.5 points in Spurrier's "Fun n' Gun" offense.
Brad Johnson completed 9-of-14 passes for 90 yards with a touchdown and two interceptions for Tampa Bay while backup Rob Johnson was 6-of-14 for 54 yards.
Brad Johnson threw a seven-yard TD pass to veteran Keenan McCardell in the second quarter for the Bucs.
Bucs fourth-round pick Travis Stephens carried 13 times for 65 yards.