Running backs Jonathan Stewart and DeAngelo Williams proved again to be a dynamic offensive duo for Carolina this past season.

They’re back for seasons to come, but the Panthers are having to deal with replacing the combined production of Greg Olsen and Jeremy Shockey at tight end.

This preseason, Olsen has shown he’s atop the depth chart at tight end. The race for the No. 2 spot is more competitive between Gary Barnidge and Ben Hartsock, and both possess different skill sets that make them attractive prospects for the backup position.

Olsen and Shockey combined for 995 receiving yards and nine touchdowns — numbers that rival top tight ends this past season. Coach Ron Rivera believes a combination of Olsen, the No.2 tight end and newly acquired fullback Mike Tolbert will equal or exceed the production from this past season.

“Some of the things Mike brings are some of the things that Jeremy did,” Rivera said. “What that does is that it allows Greg to do some of the Jeremy stuff from last year as well as his own game. It’s a good mix, and adding Mike has given us a little more flexibility.”

Shockey wasn’t re-signed by the Panthers in the offseason, and the No. 2 tight end will likely be filled by committee, Rivera said. He mentioned some have called it replacing one guy with two, but he says he’ll keep the same number of tight ends (five) on the roster as this past year.

Hartsock’s specialty is blocking, and the nine-year veteran has blocked for 2,000-yard rushing teams in six of the past seven seasons. Last year’s Panthers were one of those teams, averaging more than 150 rushing yards per game that placed them third in the league.

But, because he’s a blocking tight end, Hartsock’s stats are less than impressive. He appeared in 15 games this past season and didn’t tally a single reception. In fact, in his career, Hartsock has hauled in more than four passes in a season only twice, with the most recent coming in 2007 with Tennessee when he had 12 catches.

Barnidge is competing in his first full preseason since 2010. This past year, the fifth-year tight end broke his ankle and sat on injured reserve all season. He said Sunday his ankle is at 100 percent and believes there’s a healthy competition for reps.

Rivera was impressed with both Barnidge and Hartsock – who each caught one pass for a first down Friday against the Dolphins – as well as the younger players like Joe Jon Finley, Nelson Rosario and Richie Brockel.

“It’s kind of up in the air. The thing with (offensive coordinator Rob Chudzinski) is that he likes guys that can do a bit of everything,” Hartsock said. “That’s why Mike is here. That’s why Gary Barnidge is doing what he does. We each have our own strong suit but we all are asked to do other things.

“I’m more on the point-of-attack guy but I play some fullback. Tolbert’s a fullback but he splits out in the slot. Barnidge is more of a split out guy but he’s asked to play at the point-of-attack. I think we’re going to be variable week to week.”

But Hartsock’s blocking abilities, while always of use, could be less in demand for the Panthers this season with the addition of Tolbert. Carolina didn’t have a true fullback last year, and Tolbert not only adds to one of the most dominant backfields in the league with his rushing abilities but also with his blocking.

“I think he’s a dynamic player doing what he does, but I’ve made a career out of making a niche in doing what I do,” Hartsock said. “Thankfully there aren’t many people who do what I do, so I hope to keep marketing that.”