OAKLAND (AP) — Matt Flynn heard a smattering of boos during pregame introductions before his first start with the Oakland Raiders even started.It was a full-fledged serenade by the time he took his seventh sack and lost a fumble that led to Washington’s clinching touchdown in the fourth quarter.David Amerson returned an interception for a touchdown that helped erase Oakland’s fast start and the Redskins took advantage of the Raiders’ backup backfield to get their first win of the season, 24-14 on Sunday.With starting running backs Darren McFadden and Marcel Reece sidelined for much of the game with injuries, Flynn was able to do very little in place of injured starter and fan favorite Terrelle Pryor, who has not recovered from a concussion.Flynn heard all about it from a sellout crowd that hoped to see Pryor’s electric playmaking only to watch Flynn hold the ball too long in the pocket all afternoon.“I mean it’s hard not to hear it,” Flynn said. You just try to focus on your job and do what you can, but it’s definitely hard not to hear.”The crowd had plenty to cheer early as the Raiders (1-3) broke out to a 14-0 lead after the first quarter thanks to Rashad Jennings’ blocked punt that led to a touchdown by Jeremy Stewart and Flynn’s 18-yard pass to Mychal Rivera.Oakland hadn’t lost a lead like that after the first quarter in 15 years and the fans sensed the change of momentum early in the second quarter when Amerson stepped in front of Denarius Moore for the interception he returned 45 yards for Washington (1-3) to cut the deficit to 14-10.Flynn took six of his sacks in the final three quarters and the game essentially ended when Ryan Kerrigan had a sack-fumble recovered by Barry Cofield and Roy Helu Jr. ran it in two plays later from 14 yards to make it 24-14 with less than 7 minutes left.“I don’t think he saw the field very good today,” coach Dennis Allen said. “He was part of some of the sacks that we gave up.