Rookie cornerback Jason Verrett intercepted Oakland Raiders rookie quarterback Derek Carr at the San Diego 5 with 1:13 remaining in the game to seal a 31-28 Chargers win on the road. San Diego had gone ahead with 1:56 to play on a 1-yard touchdown run by Oliver. Verrett's first career interception helped the Chargers extend their winning streak to five, while Oakland suffered its 11th straight defeat. The Chargers 5-1 start to begin the season was their best since 2002. Carr threw a 77-yard TD pass to Andre Holmes in the opening minute of the game, and he and Rivers both threw two touchdowns in the first half for a 14-14 tie at halftime. In the third quarter, a 54-yard Novak field goal was nullified by a Chargers holding penalty. On fourth-and-35, Weddle threw an incomplete pass on a fake punt, giving the Raiders excellent field position; Oakland then scored on a 47-yard TD pass from Carr to Brice Butler. The Chargers responded with a Gates score on a 1-yard pass from Rivers, and the game was tied at 21 to begin the fourth quarter. Oakland took the lead again after Carr found Holmes for a 6-yard TD with 10 minutes left. On the following possession, Rivers completed the first four passes for 70 yards, which led to a 30-yard field goal by Novak. The Chargers defense forced a three-and-out, when Allen&#8212;filling in for an injured Royal&#8212;returned the punt 29 yards to the Oakland 39. With 4:49 remaining, Rivers led the six-play game-winning TD drive which culminated with four straight runs by Oliver for 29 yards. The Raiders had the ball on the Chargers 45 on second-and-one, when Carr threw deep for Butler, but Verrett leaped for an acrobatic sideline interception. Verrett had left the game earlier in the third quarter after tearing his left labrum in three places while diving for a pass. Oliver ran for 101 yards in the game, and Rivers threw for 313 yards and three touchdowns. For Rivers, it was an NFL-record fifth straight game with at least a 120 passer rating. Verrett grew up a Raiders fan in nearby Fairfield, California. About 100 of his friends and family attended the game, including his brother, who works for the Raiders.
Question: How many touchdown passes were thrown in the first half?
Answer: 4