CLEMSON, S.C. -- Here’s a common refrain around the ACC this offseason: Replacing a quarterback is the big story, but the more important departure might be at running back.

It’s true at Virginia Tech, as we noted a few weeks ago.

Certainly, there are similar concerns at North Carolina, too. Pitt and Miami appear to have strong options at running back, but they’re still looking to replace departed talent on teams that will be built around the ground game. Even Florida State, with some five-star talent entering the program, can’t feel completely confident it will replace Dalvin Cook without a hiccup.

But, more than any of those programs, perhaps the one with the biggest question mark at tailback is Clemson.

Wayne Gallman was a workhorse the past two and a half years, which makes him particularly tough to replace. And while the Tigers appear to have some strong options at quarterback (though, really, can anyone replace Deshaun Watson?), and experienced depth replacing the departed receivers, running back looks like the one question mark that isn’t guaranteed to have a good answer.

Start with where the production left off last season.

Clemson’s offense was excellent, obviously. But much of that success was built upon the enormous ability of Watson at QB -- a luxury the Tigers won’t have in 2017. On non-QB running plays, Clemson averaged just 4.77 yards per carry (48th among Power 5 teams), 4.74 yards-per-rush on first down (46th) and converted just 50 percent of its third-and-short (3 yards or less) runs, good for 41st among Power 5 teams, tied with … South Carolina!

It’s not that those numbers are awful, but they certainly aren’t national championship stats. It’s just that they were balanced out by a once-in-a-generation quarterback who could make plays with his arm and his legs and the rest of the ground game was largely supplemental.

Only, it’s not exactly that simple.

For one, even if Kelly Bryant or Zerrick Cooper or Hunter Johnson (who’s making a nice push for the starting job) are excellent, replacing Watson’s production is a lot to expect of anyone.

Secondly, even with Watson on the field, Clemson’s lack of a run game proved problematic last season.

In Clemson’s 14 games against FBS teams, the Tigers’ backs failed to match their opponents’ season average in yards-per-rush allowed eight times. Only three times -- against Wake Forest, Louisville and Boston College -- did they improve dramatically on what their opponents yielded, on average, for the season.

Break those numbers down a little more, and it’s clear why this is so significant.

In the six games in which Clemson performed better than what its opponents’ yielded on average, the Tigers won by an average of 27 points per game. It’s a chicken-or-egg argument, perhaps, but the point is that when Clemson ran well, it won in a landslide.

In those other eight games though? The average margin of victory for Clemson was just 12 points, and that number was inflated by a 54-point win over Syracuse. Set that one aside and the average tumbles to just 6 points per game.

In other words: Run well, and Clemson dominated. Struggle to run, and Clemson found itself in a lot of one-possession games.

The Tigers won most of those close games because Watson was so good, but what happens without him in 2017?

Thus far, it looks like veteran C.J. Fuller has a slight edge for the starting tailback job, and co-offensive coordinator /RBs coach Tony Elliott said Fuller "looked the most at ease" during Wednesday’s scrimmage.

Adam Choice knows the job, too, and Travis Etienne could add a spark when he arrives this summer.

The most intriguing name, however, remains Tavien Feaster. The sophomore flashed potential last year, but he wasn’t consistent enough to stay on the field, and that’s been a continuing concern this spring. But Wednesday’s work was promising, Elliott said.

“I saw a different level of confidence in Tavien, and part of it is, he’s a young guy, and I’m pushing him hard,” Elliott said. “He’s trying to do everything perfect. I told him to go let it loose, and I saw him running the ball.”

That’s the good news. The bad news is how Elliott ended that analysis: "But I saw some things in pass protection."

Pass protection is clearly Feaster’s biggest flaw, and it’s worth noting. A year ago, Clemson had just a 2.9 percent sack rate when opponents blitzed, the fourth-best mark in the Power 5. That’s partially a reflection of Watson’s ability, but also a number that suggests just how good Gallman was in picking up defenders in pass protection.

For now, that might be enough to keep Fuller out front, but Elliott also said there’s a good chance the battle rages on well into fall camp.

“You’d like to have some clarity coming out of spring,” he said, “but if they all continue to progress like they are, there’s not going to be a huge separation between the three of them.”

That’s fine if all three are taking big steps. It’s a problem, however, if the ground game won’t be any more productive than it was a year ago.