The Raiders started the game with 12 unanswered points off of two blocked punts and a field goal. But San Diego quickly responded with a touchdown pass by Philip Rivers and a rush by Mike Tolbert. After the Raiders and Chargers traded field goals, the Chargers led, 17-15, after the first half. Bruce Gradkowski was injured in the first half and after briefly starting the second half, he left the game. Jason Campbell relieved Gradkowski at the quarterback position for the rest of the game. In the third quarter, The Chargers and Raiders traded touchdowns and heading into the fourth quarter the Raiders trailed, 24-22. In the 4th, Nate Kaeding kicked a field goal early and extended the Chargers' lead to five, 27-22. The Raiders then capped off a 14-play, 73-yard drive with a rushing touchdown by Michael Bush, who took back the lead. After a failed two- point attempt by Oakland, they led, 28-27, with 3:24 remaining in the ballgame. The Chargers than began to drive trying to get themselves into field goal position to win the game. The Chargers eventually made it to the Raiders 23-yard line, but after a 10-yard holding penalty by the Chargers, San Diego faced a 2nd and 20 on Oakland's 33-yard line. Looking to pass, Rivers was stripped by Michael Huff and Tyvon Branch returned the fumble 64&#160;yards for a touchdown, sealing the win for the Raiders, 35-27. Though the Chargers outgained the Raiders, 506-279, their special teams were ultimately the deciding factor, giving up two blocked punts for a safety and touchdown. With the win the Raiders not only improved to 2-3, but also snapped a 13-game losing streak to the Chargers, with the first win over the Chargers since September 28, 2003.
Question: What Raiders position was replaced in the second quarter?
Answer: quarterback