Chargers sign QB Kyle Boller

Quarterback Kyle Boller signed a one-year deal with the San Diego Chargers on Friday.

Boller, a first-round pick of the Baltimore Ravens in the 2003 draft, played the past two seasons with the Oakland Raiders. Last year for Oakland, Boller played in two games, completing 15 of 28 passes for 161 yards and three interceptions.

Boller is expected to provide insurance at QB to the Chargers, who lost Charlie Whitehurst on Thursday when he rolled his left leg during a practice session.

According to the San Diego Union-Tribune, Billy Volek, who had been the Chargers' backup from 2006-12, turned down a contract offer from the team Thursday.

Starter Philip Rivers and Jarrett Lee are the other quarterbacks on San Diego's roster.