Playing their first road game in three weeks, the Vikings traveled to Lambeau Field to play their long-time rivals, the Green Bay Packers. In the first half, a 30-yard run by Ryan Grant would give the Packers a 7-0 lead, and two field goals by Mason Crosby (a 39-yard field goal midway through the 2nd quarter and a 24-yard field goal at the end of the half) would provide all the first half scoring, as the Vikings went to the locker room trailing 13-0. The Packers completed the shutout with Brett Favre throwing a pair of third-quarter touchdown passes, one to Donald Lee and one to Ruvell Martin. Martin would score again in the fourth quarter. The Vikings were shut out 34-0, the first time the Vikings had been shut out in the regular season since 1991. Adrian Peterson suffered a knee injury in the third quarter and left the game. With the loss, Minnesota fell to 3-6 and were swept by the Packers.
Question: How many points did Packers score in the second half?
Answer: 21