SPARTANBURG, S.C. (AP) -- The Carolina Panthers have settled some questions at wide receiver.
''Those three guys have really stepped up and have really showed that they've meshed very nicely,'' Rivera said Tuesday as the Panthers wrapped up their 20th training camp at Wofford College.
Rivera also said the Panthers have a ''good handle'' on their revamped offensive line, but are still looking for answers at cornerback.
The Panthers opened camp July 25 with virtually an entirely new slate at wide receiver after parting ways Steve Smith, Brandon LaFell and Ted Ginn Jr.
Benjamin is helping fans forget about Smith, the team's all-time leading receiver.
The 6-foot-5, 240-pound Benjamin's popularity in the Carolinas has soared after a strong training camp and a spectacular stumbling, diving catch in the end zone in the Panthers preseason opener against Buffalo.
As Benjamin left the practice field Tuesday, hundreds of fans began chanting ''Kel-vin! Kel-vin!'' in unison while trying to lure him over to sign autographs.
Rivera said that while he's pleased with Benjamin, he cautioned the rookie still has plenty of room to improve after playing just two seasons at Florida State.
''We saw him do the things we needed him to do, but it's not just about going out and making great catches,'' Rivera said. ''It's about knowing the offense. It's about doing the things within the offense. And there's some things that if teams are doubling you, or teams are rolling to you, they're trying to take you out. And if you're not doing things within what we're trying to do, that can hurt us. So he's young. He's got a lot to learn.''
Benjamin understands that.
He said he plans to continue to study the playbook so he can play faster on the field, saying ''You can always get better.''
As for the fans chanting his name, Benjamin looked over and said, ''I think they're excited for a receiver to come in and start making plays for them. I think everybody is.''
Benjamin has been running with the starters alongside Cotchery, who caught 10 touchdown passes last season for the Pittsburgh Steelers.
Avant has been the No. 3 receiver.
Carolina's offensive line also underwent rampant change this offseason with four players retiring, including longtime left tackle Jordan Gross.
The starting offensive line hasn't wavered much since the start of training camp with last year's right tackle Byron Bell moving to left tackle. Nate Chandler has been working at right tackle with Amini Silatolu and rookie Trai Turner at guard.
Three-time Pro Bowler Ryan Kalil still anchors the line at center.
''I think there is going to be some growing pains with this group than some of the older groups we have,'' Kalil said. ''But we have some really tremendous talent that I think will set us up for years to come.''
Defensively, the Panthers return their entire front seven from last year's No. 2-ranked unit, but Rivera said questions remain in the secondary.
He hopes to have that sorted out in the next couple of weeks.
''I'm not quite as concerned about safety as I am corner,'' said Rivera, last year's NFL Coach of the Year.
Rivera said the biggest disappointment at training camp was the weather.
It wasn't hot enough for him.
Surprisingly cool temperatures and rain were commonplace this summer during the team's 18-day span in Spartanburg.
Several players cramped up at practice the last two days and Rivera said he's worried the lack of heat will affect the team's conditioning in Week 1 when the Panthers open at Tampa Bay.
''When we go down to Tampa Bay it's going to be hot,'' Rivera said. ''There's a toughness that gets built out of practicing in the heat, and we didn't have enough of it, in my opinion. So hopefully we can get a real good shot of heat in the next week or so.''
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