Conversely, Buckeyes quarterback J.T. Barrett can throw but can't yet run.
That leaves Cardale Jones as the only returning Ohio State quarterback who can do everything in spring practice.
While the injuries might not be the most ideal situation for defending national champion Ohio State, it isn't the worst scenario imaginable. If Barrett and Miller can't fully participate in spring practice, they technically can't lose the starting job. And that's why all three might still be on campus when the Buckeyes open preseason camp in August.
August is when Ohio State's pressure cooker scenario really begins. Perhaps never before have three quarterbacks who accomplished so much in college football battled for one starting job. It will be one of the most-watched position battles in recent history.
"Somebody asked me if I was stressed about it," Ohio State coach Urban Meyer told ESPN.com Thursday. "Not at all, because Plan A is good, Plan B is good and Plan C is really good. I don't know what it is. The stressful part is when you start thinking about the people involved, and they're great people."
Even better, they're three very good quarterbacks. Miller, a senior from Huber Heights, Ohio, was a two-time Big Ten Offensive Player of the Year before suffering a season-ending shoulder injury during preseason camp in 2014. Barrett, a sophomore from Wichita Falls, Texas, was thrust into the lineup after Miller's injury. Barrett played so well in 12 starts that he was considered a Heisman Trophy candidate until he suffered a broken ankle against Michigan in the regular-season finale.
So Jones started the final three games and led the Buckeyes to victories over Wisconsin in the Big Ten championship game and Alabama and Oregon in the inaugural College Football Playoff.
"There's always been a competition," Jones told reporters on Thursday. "You guys are making a big deal out of it now because you've seen all of us play. It's always been this way."
Despite how well he played at the end of the 2014 season, Jones, a junior from Cleveland, might actually have the most ground to make up. Even though he easily has the strongest arm among the contenders, he has the least experience, even after directing the Buckeyes' improbable championship run. At least Meyer and his staff now know what Jones is capable of doing.
"That wasn't against lower-level opponents in noon games on Saturday in front of 22,000 people," Meyer said. "The first start of his career was the Big Ten championship game, the second start was against Alabama and the third start was for the national championship. It's unbelievable when you think about it. In the history of college football, has that ever happened? In the history of this great game, has that ever happened with a third-string quarterback?"
But last season won't matter in this year's competition. At the end of the day, Jones still has only three college starts under his belt, far fewer than what Barrett and Miller have.
"The thing that disappoints you as a coach sometimes is that you don't want to say he's wasted time, but he has. If he'd attacked everything like this for years, he would have been a far more advanced player. He's catching up quickly."Urban Meyer on Cardale Jones
"The thing is he learns really fast," Meyer said. "The thing that disappoints you as a coach sometimes is that you don't want to say he's wasted time, but he has. If he'd attacked everything like this for years, he would have been a far more advanced player. He's catching up quickly."
With Jones getting most of the reps with the first-team offense during spring practice, Barrett and Miller might have to play catchup this summer. Miller has been able to do only some light throwing after suffering a torn labrum in his right (throwing) shoulder during preseason camp in August, and has been limited to practicing his footwork and passing drops. Miller stands about 10 yards behind the Buckeyes' offense during team drills so he can at least read pass coverage and go through his progressions mentally.
"He's as engaged as he's ever been," Meyer said.
Barrett, who went 11-1 as Ohio State's starter in 2014 and passed for 2,834 yards with 34 touchdowns and 10 interceptions, has been able to make every throw in practice. Barrett is also participating in some 7-on-7 drills, but the Buckeyes aren't putting him in a position where a defender might hit his surgically repaired right ankle. Barrett had surgery in mid-February to remove two screws from the ankle.
"I can't rush it," Barrett said. "I'm not going to rush it."
And neither is Meyer, who doesn't figure to make a decision on his starting quarterback until deep in preseason camp. Miller has said he'll be back at Ohio State this season, and Meyer said he doesn't have any reason to think he won't. Miller, who didn't talk to the media after Thursday's practice, graduated from Ohio State in December, so under NCAA rules, he is eligible to transfer to another school and play immediately.
Meyer has ruled out moving Miller to another position and doesn't plan on playing two quarterbacks in 2015.
"I'm not Braxton, but being that I do talk to him every day, I ... would be shocked if he was to leave," Barrett said. "I think it's ridiculous, honestly."
Right now, who starts at quarterback isn't Meyer's biggest concern. Getting each of his three quarterbacks healthy is what matters most.
"I don't want to say I've been ignoring it because I haven't ignored it," Meyer said. "Each player and each day is different. We're trying to handle a Thursday practice, and we're not worried about August or September."