Starting at quarterback in major college football is an immense challenge. Doing it as a true freshman? It can be overwhelming.

Talk to a highly regarded quarterback recruit and playing early is often the goal. Now more than ever, quarterbacks want to see the field quickly.

Some hit it big, but most don’t. According to ESPN Stats and Information, in the past five seasons only 13 true freshman quarterbacks at Power 5 programs ranked in the top 100 nationally in passing efficiency at the end of their debut season. Only three -- UCLA’s Josh Rosen (2015), Miami’s Brad Kaaya (2014) and Cal’s Jared Goff (2013) -- threw for 3,000 yards as true freshmen, while two others came close (Washington’s Jake Browning this past season and Penn State’s Christian Hackenberg in 2013 each passed for 2,955 yards).

Yet every season a few teams will turn to an 18- or 19-year-old to lead the way at the most important position. Georgia, with No. 1 quarterback recruit Jacob Eason, could be next in line.

No. 1 quarterback recruit Jacob Eason could be in line to start for Georgia as a true freshman. Tom Hauck for Student Sports

What does it take to do it? What challenges do they face and how do coaches know when they're ready? The answer varies.

"It's like a rookie quarterback in the NFL: Can he handle it?" Boise State coach Bryan Harsin said. "You don't know those things because the test hasn't been given yet."

One reason the trend is increasing is quarterbacks are more prepared to play immediately now than they were 20 years ago.

“Guys have a chance to work on their skill sets -- it's almost specialized -- all year long,” Texas A&M offensive coordinator Noel Mazzone said. “They have [private] quarterback coaches, they're going to all these camps ... they're going out every weekend and throwing 7-on-7. It didn't used to be like that in the old days. You'd play other sports and there weren’t all these 7-on-7 leagues, or the Elite 11 or The Opening and all this stuff.”

For some prep passers, working year-round is the reality. Private coaching -- which has become big business -- allows quarterbacks to spend extra time outside of their regular high school football season improving their games.

That’s not the case for everyone, though. Marshall quarterback Chase Litton, who started 11 games as a true freshman in 2015, played three sports in high school.

“When I finished football I went into basketball season. When I finished basketball I went into track,” Litton said. “I was always active. I felt like basketball and high jump really helped me with my feet and conditioning on the football field and helped me stay in shape.”

Litton worked with a private coach in the offseason to improve his footwork but didn't throw every day. It didn’t appear to hinder him: He threw for 2,605 yards, 23 touchdowns and only eight interceptions as a true freshman for the Thundering Herd last season.

Missouri quarterback Drew Lock was good enough on the hardwood to earn Division I basketball offers, and while he said playing hoops in the summer may have sometimes taken time away from improving as a quarterback, he has no regrets.

In most cases, enrolling early in college is key. Getting an entire semester of classes, work in the weight room and spring football is something most coaches feel is beneficial for a starting quarterback-to-be.

“I think it really, really helps them, without a doubt, because then they're not a freshman when they get to camp,” Mazzone said. “They've gone through all this stuff. They know your offense, they know what's expected of them. They've been going to class, they've been living the college life, so it's not thrown on them all of a sudden.”

Rosen, Browning, Litton and Boise State’s Brett Rypien are all examples of players who arrived on campus in January 2015. Litton said, “I couldn't even imagine being able to play [right away] without it.

“When spring came, obviously, the first week, two weeks, you've got to adjust to the speed, the stature of the guys, the knowledge of the game, the coverages you're going to get, the looks you're going to get,” he said. “I remember thinking after the first day of spring ball: 'Dang, I really have to improve, because this is college football.'”

It’s not always the case: Lock didn’t arrive at Mizzou until June. That's also when Lamar Jackson, who finished the season with the highest Total QBR (72.0) of any true freshman in 2015, arrived at Louisville. Jackson started eight games for the Cardinals and had a landmark performance in their bowl win over Texas A&M (227 passing yards, 226 rushing yards, four combined touchdowns). He set single-season school records for rushing touchdowns by a quarterback (11) and rushing yards by a quarterback (960) in 2015.

In most cases, coaches recommend getting the extra time in the spring if the quarterback has his sights set on playing immediately.

Stepping on the field for the first time can be dizzying. Lock said the first time he saw the field, as a backup against Southeast Missouri State, he was “practically hyperventilating.” When he made his first career start a month later against South Carolina, he also had to calm his nerves. Once he settled in, the next thing he had to do was adjust to the speed of the game, which many freshmen say is one of the most challenging parts of starting.

“You have 300-plus-pounders moving at the speed of the fastest guys in high school you would see,” Lock said. “You have corners out there that you've ever seen in your life. You're throwing at targets that are faster than guys you ever have. And it's hard not to think about pressure out there. You have a whole state and university relying on you. You're the face of it. That was difficult.”

For some, like Rosen, it’s easier to digest. Mazzone, who coached Rosen at UCLA last season, said Rosen's transition was smooth.

“One of the most gifted kids I've ever been around,” Mazzone said. “Very, very smart. He gets the game. [Some freshmen are] waiting for the day that the game slows down. It's been slow for Josh forever.”

Injuries often dictate timing. In Boise State’s case, Harsin wanted to redshirt Rypien behind Ryan Finley, who was the starter heading into 2015. After an early-season injury to Finley, Rypien stepped in and responded with 3,353 passing yards, 20 touchdowns and eight interceptions in 11 games (10 starts).

“Sometimes having young players, or in this case a true freshman, it's not all that bad,” Harsin said. “Young players don't know all the bad. I don't want to say this in a negative way, but they're just dumb enough to find ways to win because there's that confidence. I think we all have that instinct in things that we do.”