The unwanted label began sticking to Alex Collins in college, even as he became the rare runner to string together three 1,000-yard seasons in the Southeastern Conference.
It hampered him as he tried to get his NFL career off the ground with the Seattle Seahawks, and now, it has him on shaky ground in Baltimore, despite the fact that he's been the Ravens' most exciting and productive runner in recent weeks.
It's the last thing any skill-position player wants to be called. Critics throw it around as if it's the name of some infectious disease.
Yet Collins does not shy away from discussing his difficulties with ball security. He does not view fumbling as some mysterious affliction. Rather, he sees it as one of the many specific problems he has to work on if he's going to establish himself as a long-term NFL regular.
"Most definitely it's something that's fixable," Collins says. "It's just mostly awareness. As a running back, you can't make it in this league if you don't have good ball security, and that's the thing. Every running back has great ball security until they're unaware of where the defense is coming from. That's the main reason why it happens — they hit you when you least expect it. So the easiest way to fix it is just to be 100 percent aware of the ball at all times."
Ravens coach John Harbaugh agrees with him, despite saying Collins was on a short leash after he fumbled for the second time in three games in Sunday's 26-9 loss to the Pittsburgh Steelers.
"We're working on the way he carries the ball, technique-wise," Harbaugh says. "I do think, in his case, that he can be corrected. I think he is very conscientious of it. I feel the same way about all of our guys; I don't think we have any 'fumblers.' Once you feel a guy is a fumbler, you're pretty much done with him."
Collins, 23, can also take heart from the fact that some of the most productive backs of the past 20 years, from Tiki Barber to Adrian Peterson, confronted and overcame fumbling problems.
Barber is probably the patron saint of fixing a fumbling malady. From 2000 to 2003, the four seasons in which he emerged as a featured back for the New York Giants, he fumbled a whopping 35 times. But in his last three seasons, when he averaged 335 carries and 1,680 yards, he fumbled nine times total.
Barber addressed the problem by keeping a football clutched to his chest at a 45-degree angle, no matter where he went.
"It became second nature," he told Newsday in a 2013 interview. "I even have to tell my kids, 'If you're going to carry the ball, you have to carry it like this.' "
He also made a habit of clamping his noncarry hand on the wrist he had wrapped around the ball so he'd be less vulnerable in traffic. As a byproduct of that attention to technique, he said, he became a more balanced and powerful runner.
"It's so much of a mechanical thing," Barber said in the Newsday interview. "It's fixable. The key is awareness of when contact is coming."
Teams take many different approaches to teaching ball security.
Some, including the Ravens, have practiced with "High and Tight" footballs, which beep incessantly if held at the proper angle and with sufficient force. The balls were designed by Tom Creguer, an assistant coach at Division II Northwood University in Michigan, who says they've substantially reduced fumbles for his teams.
Peterson, the 16th-leading rusher in league history, had a performance trainer try to punch the ball out with boxing gloves while he ran against a resistance device and practiced holding the ball securely as he rolled through jiujitsu drills, according to a 2016 ESPN.com piece.
New England Patriots coach Bill Belichick, generally regarded as the best in the business, is almost manic about avoiding fumbles. He rarely drafts players who cough up the ball regularly in college, and he has his skill-position players practice with wet and warped footballs so they're used to securing the ball in suboptimal conditions.
Collins, who fumbled 17 times in three college seasons at Arkansas, sounds almost exactly like Barber when describing what he's doing to fix the problem. He says that every time he touches a football, even in a casual setting, he's mindful of clutching it in a tight grip, wrist above the elbow and elbow clamped to his side.
"I've always got the ball ready now," he says. "It's just a habit thing. That way, you don't have to worry about protecting it at those times, when you don't know where everyone is, because you already have the ball protected out of habit. It becomes second nature."
He also practices bringing his noncarry hand across to lock his wrist in place around the ball.
That technique broke down against the Steelers, when linebacker Ryan Shazier pulled Collins' right arm away from the ball, and then defensive end Cameron Heyward hit his left, or carry arm, popping the ball loose.
Defenders practice targeting the ball as much as the man, so Collins knows he can't give them any angles of entry.
Fellow Ravens running back Buck Allen worked through his own struggles with ball security in 2015, and he says there's no great mystery to it.
"A guy that fumbles, he knows the reason why he fumbles," Allen says. "He's just got to work on it every day. You have to practice your craft. … I really don't put focus on it. You just try and get in the habit of locking your wrist and being careful with the ball."
The unfortunate thing for Collins is that one of his best attributes — a grinding will to extend runs after he takes an initial hit — also makes him vulnerable to fumbles.
"I've just got to do a better job of keeping two hands on the ball when I go in those piles," he says. "I like to fight for extra yards and not let that first person tackle me, but sometimes, fumbles happen when you're straining and fighting so hard. I'm not going to change my mindset or my mentality. I'm just going to do it with two hands from now on."
Collins has to walk a careful line between retaining his tenacious style and hitting the ground when the time is right.
Ravens quarterback Joe Flacco says it's a problem to which he can relate. Sometimes, when he's forced out of the pocket, he has to fight his instinct to hold the ball too long or throw a high-risk pass into traffic. When he's less judicious, turnovers follow.
"It's just part of the IQ, probably part of common sense sometimes about when you're fighting too long, when you know the play is over and you have to get down," Flacco says. "With Alex, it is the same thing — just the way you hold the football, [knowing] when fighting for extra yards is a good thing, and when you just have to call it quits and get what you got."
The Ravens have ample reason to hope Collins stops fumbling, because he's been one of their few offensive standouts in recent weeks. He bounced back from his fumble against the Steelers to rip off a 50-yard run in the second half. And with 206 yards on 25 carries, he's been far more productive than Terrance West, the team's starter coming into the season.
Given that the Ravens signed Collins to their practice squad after the Seahawks dumped him, he could go down as a memorable find. Or, if he fumbles again, he could disappear from the lineup as fast as he crashed it.
Collins understands the stakes but says he has little doubt he will put his troubles behind him.
"I don't lose any sleep about it," he says. "One week, my problem might be how I ran my routes, that I didn't get deep enough. Or it might be missing my landmarks, getting too wide on my runs, another week. Last week, it happened to be my ball security. I'm going to work on it, fix that and just keep moving forward."