Updated

SPARTANBURG, S.C. (AP) Ron Rivera said he'll be paying particularly close attention to his team's wide receivers and defensive ends when the Panthers open the preseason Friday night at Buffalo.

Carolina is deeper than it has ever been at wide receiver in Rivera's five seasons, which has made for good competition at training camp and tough decisions ahead.

Kelvin Benjamin, Devin Funchess, Jerricho Cotchery and Ted Ginn Jr. appear to be locks to make the roster, but there's a crowd behind them fighting for roster spots including Corey ''Philly'' Brown, Brenton Bersin, Mike Brown, Jarrett Boykin and Damiere Byrd.

''We've got five or six or seven guys right now that are battling,'' Rivera said. ''We really haven't projected anybody as clear-cut, top five or six. But we've got a group of guys that are showing every day. They flash constantly.''

Rivera is also anxious for someone to step up and win the team's vacant starting right defensive end spot opposite Charles Johnson.

Frank Alexander, who missed 14 games last season serving a suspension for violating the league's substance abuse policy, appears to be the leading candidate. However, 2014 second-round draft pick Kony Ealy, Wes Horton, and pass-rush specialist Mario Addison figure into the mix and Rivera is hoping some young players step up and make noise.

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Some other areas to watch to as the Panthers head into the preseason:

CAM'S BLINDSIDE: Michael Oher was brought in to replace Byron Bell as left tackle, even though he struggled last season with Tennessee. Oher, who got a two-year, $7 million deal, is viewed as a stopgap for the Panthers until they can draft a top-notch offensive tackle or sign one. But it's vital that he does a good job protecting Carolina's $103 million investment in quarterback Cam Newton.

NEWTON'S TIME: Newton will play about a quarter against Buffalo. Offensive coordinator Mike Shula found something he liked with Newton running the no-huddle late last season and the Panthers may work some of that into their game plan.

THOMPSON'S ROLE: The Panthers drafted Shaq Thompson from Washington in the first round thinking he would be a great long-term replacement for Thomas Davis and add speed and athleticism to an already fast and athletic front seven.

NORMAN'S RISE: Defensive backs coach Steve Wilks has said Josh Norman has what it takes to be a star cornerback in the NFL. Entering a contract year, Norman has had a very solid camp, although he garnered most of his attention for getting into a scrap with Newton at camp. Norman is expected to be paired against wide receiver Sammy Watkins, a good first test.

RED ZONE SUCCESS: Carolina was one of the worst teams in the league last season in the red zone and has struggled some with that in training camp. The Panthers need to find more ways to score touchdowns rather than settle for Graham Gano field goals. Expect to see more lob passes to Benjamin in the end zone.

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