Melvin Gordon, who grew up idolizing Adrian Peterson, is working with the veteran running back on ball security this offseason.

Gordon has joined Peterson for offseason workouts in Houston.

"I talked to Adrian about it, and he said, 'The biggest thing about the lack of ball security is, it's a mental thing,'" Gordon said. "You can do a lot of drills, but you can still go out there and mess up if you're not mentally focused on it. It's [having that reminder of], 'Someone's there. Someone's always there [trying to take it].'"

Peterson fumbled seven times last season, losing three, after not losing a fumble in 2014.

Gordon fumbled six times as a rookie.

San Diego voters will decide in November on a proposal by the Chargers to raise local hotel taxes for a downtown stadium and convention facility.

City Clerk Liz Maland says the football team had secured enough valid signatures to qualify the measure for the 2016 ballot.

If approved, the proposal could keep the team from moving to the Los Angeles area, where it has been approved by NFL ownership to join the Rams in a new stadium being built in Inglewood.

San Diego voters will decide in November on the Chargers' proposal to raise local hotel taxes for a downtown stadium and convention facility.

If approved, the proposal could keep the team from moving to the Los Angeles area, where it has been approved by NFL ownership to join the Rams in a new stadium being built in Inglewood.

Chargers chairman Dean Spanos expressed appreciation to those who signed petitions. "We gathered more than 110,000 signatures in less than six weeks, an extraordinary result that demonstrates the high level of community interest in a new multi-use stadium and convention center facility downtown," Spanos said.

The Chargers would contribute $650 million for the stadium portion of the project, using $300 million from the NFL and $350 million from the team, licensing payments, sales of "stadium-builder" ticket options to fans, and other private sources.