With that in mind, let's whet our appetites for some big spring storylines by looking at 10 stars departing for the pros and who figures to step in and fill their shoes in 2019.
Who's out: Quinnen Williams
Who's in: Phidarian Mathis, Christian Barmore
Concern level: Moderate
Let's be honest: Alabama rarely needs to be concerned about replacing talent. This happens every year, as NFL-level talent departs for the pros and the next line of elite recruits fill the void. That is the case again in 2019, and Mathis and Barmore have the credentials and physical assets to become stars in their own right. But two things stand out as potential red flags. First, Williams was special. He wasn't just talented; he changed games. There was no more disruptive influence on defense in the country. That's not plug-and-play. Even at Alabama, those guys are rare. Secondly, this isn't the same Alabama defense as in years past. The 2018 Tide surrendered more points per drive, rushing TDs, total TDs and yards-per-play than in any season since Nick Saban's debut in 2007. All of that happened with Williams leading the defense to one of the best sack rates of the Saban era.
Who's out:Dwayne Haskins
Who's in: Justin Fields, Matthew Baldwin
Concern level: Minimal
The biggest concern for Ohio State right now is less about the talent on the roster and more about the decision of the NCAA on whether to grant transfer Justin Fields immediate eligibility. With Tate Martell's decision to transfer, it sure seems like there's an expectation that Fields will be the starter for 2019, and if he is, it's less about replacing Haskins -- a more traditional pocket passer -- and more a return to the J.T. Barrett era of dual-threat QBs for the Buckeyes. That could be a boon for the Buckeyes' offense, which saw its tailbacks average just 1.85 yards before contact per rush last year -- down from 4 yards per rush with the mobile Barrett at QB. Forcing defenses to account for the QB run has a trickle-down effect, and Fields' arm is better than Barrett's to boot. He has superstar potential.
Who's out: Gardner Minshew
Who's in: Cammon Cooper or Gunner Cruz Concern level: What, Mike Leach worry?
Minshew's performance in 2018 changed the game for Washington State, putting the Cougars in the national spotlight and giving the program legitimate playoff hope for much of the season. But given Minshew's circuitous route to Washington State, he also offered a reminder that Mike Leach can do a lot with a QB, even if he isn't a hot commodity. That's the hope for Wazzu in 2019, too, as either Cooper or Cruz would appear to be in line to take over the job if Leach doesn't land another transfer. Eastern Washington's Gage Gubrud has narrowed his options to Washington State and Utah, so he could inject some excitement into the mix, too, but the optimism here comes as much from Leach's history as the guy actually taking snaps.
Who's out: Christian Wilkins, Austin Bryant, Dexter Lawrence and Clelin Ferrell
Who's in: Jordan Williams, Xavier Thomas, Justin Foster, Nyles Pinckney
Concern level: Minor anxiety
For the Tigers, this might be less about replacing the talent and more about replacing the personalities. For as good as Wilkins, Ferrell, et al., were at Clemson, there are folks inside the program who think Thomas has a chance to be better than any of them. Besides, defensive coordinator Brent Venables has a history of replacing elite defensive linemen with more elite defensive linemen. What is different this time around is that the four departing stars were among the biggest personalities in the locker room, the guys who dictated the culture from the weight room to the practice field to game day, and a unit that never missed the playoff. That leadership doesn't have to come from the linemen's immediate replacements, but it is certainly a sizable void.
Who's out: Jake Browning
Who's in: Jacob Eason
Concern level: Minimal
There's no replacing experience, as the coaching cliché goes, so that's a knock on Browning's replacement. Browning has been synonymous with Washington football for four years, and that type of stability isn't something another QB can offer. But the reality is Browning occasionally left Washington fans scratching their heads, and the offense, far too often, appeared limited. In the past four years, Washington is 33-1 when scoring 28 or more points, but the Huskies managed that total just five times last season. Eason has had a year to run the scout team, learn the Huskies' offense and build trust within the locker room, and his talent is unquestioned. There's every reason to believe Eason can step in and succeed immediately. The bigger question is whether he can take Washington's offense to the next level.
Who's out: Kyler Murray
Who's in: Jalen Hurts
Concern level: Cautious optimism
In 2017, a transfer QB leads Oklahoma to the playoff and wins the Heisman. In 2018, a different transfer QB leads Oklahoma to the playoff and wins the Heisman. So, when a talented transfer arrives to take the starting job for 2019, why worry? Well, there are a few differences between Hurts and his predecessors, Murray and Baker Mayfield. Both Murray and Mayfield had time in the system before assuming the starting job, and while both were hyped, neither came with the immediate spotlight that will be on Hurts. The upside is that Hurts is a proven winner and a great locker room guy, and while he's a less explosive passer than Murray, he offers the same dual-threat possibilities. Hurts should be just fine leading the Sooners' offense, but if Oklahoma can't find some answers on D, it might be a bit too much to ask Hurts to carry the burden Murray did last year.
Who's out: Julian Love
Who's in: Donte Vaughn, TaRiq Bracy
Concern level: High
The Irish got a taste of life without their star corner in the Cotton Bowl, in which Love departed with an injury and Clemson QB Trevor Lawrence utterly shredded Vaughn in Love's absence. For all the talk of a blowout in that game, it isn't hard to envision a much closer affair if Love had been on the field. Luckily for the Irish, they won't be facing Lawrence again anytime soon, but they led Power 5 programs, allowing just 5.35 yards per pass in the regular season last year, and that's going to be a tough number to match without Love on the field. Meanwhile, it's fair to ask how much damage was done to Vaughn's psyche during the Cotton Bowl, which could open the door for Bracy or someone such asHouston Griffith, who played nickel last season, to step up instead.
Who's out:Jarrett Stidham
Who's in: Bo Nix, Joey Gatewood, Malik Willis
Concern level: Moderate
This is arguably the most intriguing QB battle of the offseason. For one, Auburn might not be finished looking for candidates for the job. The Tigers were in on Kelly Bryant before he committed to Missouri, and as more battles shake out elsewhere, Jordan-Hare Stadium could be a nice landing spot for several others. But if left to pick from the guys already on the roster, Gus Malzahn seems optimistic that he'll find a good answer. Still, it'll be a fresh start. None of the QBs -- including incoming freshman Bo Nix -- has significant experience, and it figures to be a pretty wide-open competition. Malzahn has favorably compared Gatewood's physical attributes to Cam Newton (dial it down a bit, Gus!), and Nix (son of former Auburn star Patrick Nix) is one of the nation's top dual-threat recruits. So there's no lack of talent, no lack of intrigue and no lack of stress on Malzahn to pick the right guy.
Who's out: Greedy Williams and Devin White
Who's in: Derek Stingley Jr./Kelvin Joseph, Micah Baskerville/Jacob Phillips/Patrick Queen
Concern level: Have you seen the offense?
LSU doesn't fret over defense. The Tigers are as close to plug-and-play as anyone outside of Tuscaloosa on that side of the ball, so no matter that Williams and White were dominant forces or that they'll both likely be top-15 draft picks. There's more talent waiting in the wings, with particular interest in Stingley, one of the nation's top recruits and a superstar corner in the making. Replacing White in the middle of the D is a slightly bigger job, one LSU got a taste for during the first half against Alabama last season. The Tigers managed just fine then, and they have a bit more time to prepare this time. Phillips is a veteran and can handle defensive playcalling, while Baskerville and Queen have huge upside, too. The big question is whether there's any wiggle room for the defense if LSU can't find more success on the other side of the ball.
Who's out: McKenzie Milton
Who's in: Darriel Mack Jr., Brandon Wimbush
Concern level: Breaking a sweat
Mack filled in admirably after Milton's injury in the regular season finale, but he'll need to take a step forward as a sophomore to keep the job and keep UCF's offense humming. Getting Wimbush as a graduate transfer was a good Plan B. He is a winner, a legitimate dual-threat QB, and a good downfield passer. That all fits nicely with Josh Heupel's system, which should ensure there's not a steep drop-off in 2019. Still, Milton's a unique talent who has led UCF's rise to prominence, so even if Wimbush largely performs like his 2017 season rather the one that got him benched last year, it's not necessarily a smooth transition. The good thing for UCF is, while Mack or Wimbush will be tasked with replacing Milton's on-field production, Milton will still be around the team to offer the off-field leadership he's provided the previous two seasons.
The way too early CFB top 25 of 2019
After Clemson crushed Alabama in the College Football Playoff, Mark Schlabach lists his top 25 college football teams of 2019.