COSTA MESA, Calif. (AP) The Los Angeles Chargers must choose between potential and experience when they select the next primary backup to Philip Rivers.

Cardale Jones has displayed in one NFL game the tantalizing physical tools he showed in leading Ohio State to the 2014 national title. Geno Smith made 30 starts in his first two seasons, but has attempted just 92 passes since 2014.

''It's kind of a position where we both need to prove our worth,'' Jones said.

Offensive coordinator Ken Whisenhunt has not yet decided how to split up the critical game reps between Smith and Jones in the preseason opener at Arizona on Saturday, but said it would likely be close to the even distribution they have shared during OTAs and training camp. The approach seems to have worked so far as Whisenhunt is pleased with the progress both have shown.

The willingness of Jones, who was acquired in a trade with Buffalo last year, and Smith, who signed a one-year contract with the Chargers as a free agent in April, to work together is a positive sign.

''The guys, they communicate,'' Whisenhunt said. ''They pull for each other, but they're very competitive, which is what you want.''

Jones credits his collaborative spirit to working with Rivers, something that became evident in his first training camp with the Chargers.

''Just being in a room with Philip for a week, I felt like I wasn't in the NFL the year before because of the knowledge he was able to provide,'' Jones said.

That relationship also allowed Jones to realize that being a quarterback takes more than a big arm or raw athleticism. Those traits propelled him into the spotlight starting the final three games of the Buckeyes' national championship run, but Whisenhunt sees Jones being better able to operate in a structure going into his third NFL season despite attempting 11 career passes.

''It has been exciting to see the way Cardale has grown up,'' Whisenhunt said.

''You understand guys are a lot better and faster,'' Jones said. ''You need to do things different and that's what I can say (now).''

Smith has a clear edge in game action. He has appeared in 35 games and has a 12-19 record as a starter. Being in both roles has shaped his understanding of how the backup has to approach his role.

''The most important attribute is to be ready every single week. You never know when your number is going to be called,'' said Smith, who has thrown 29 touchdown passes and 36 interceptions.

Backing up Rivers has largely been a theoretical exercise since he became the starter in 2006. Rivers has started 192 consecutive games, the longest active streak in the NFL at any position. Kellen Clemens attempted eight passes as Rivers' backup last season, all with the Chargers leading by at least 24 points.

Still, Whisenhunt said the criteria for choosing a backup does not change because of Rivers' remarkable dependability.

''The right answer for me is that I want a guy that can go in there and win if your starter is out,'' Whisenhunt said. ''You don't ever want to lose your starting quarterback, but if you feel like you have a guy that has shown that he can go in there, handle it and do well, it's a really good feeling.''



By DAN GREENSPAN