The first year the NFL allowed underclassmen to apply for its annual draft, 28 players with college eligibility remaining left school early for the promise of riches in professional football.

Five of those players were chosen among the first 10 picks in 1990 — led by Illinois quarterback Jeff George by the Indianapolis Colts with the first-overall pick — with 10 not selected at all.

Those numbers across the board have gone up exponentially in the ensuing three decades, topping out with a record 144 players applying to come out early in 2019.

Of that total, however, 49 went undrafted — a whopping 34 percent for the second consecutive year. And that figure remains a problem for a system that, unlike basketball, does not allow players to make the determination to return to college ahead of the draft if it does not appear the process will work out for them.

“I think players realize there’s a short window for a career and you’re not being paid in college, so let’s try to go to the NFL and get paid. I think it’s really that simple,” former Giants offensive lineman Geoff Schwartz, host of the “Block ‘Em Up” podcast, said in a phone interview last week. “I think a lot of players take the risk, just because they or their family needs the money.

“They’d rather try to get to the NFL, even if you’re undrafted, to make a roster or even make a practice squad, taking that chance economically, that makes more sense for a lot of guys than staying one more year.”

A deeper dive into numbers provided by the NFL shows that 1,542 players have left college early for the draft since 1990, and 1,111 of those were chosen (72 percent), including 151 within the top 10.

This year, 115 players with remaining eligibility declared and were granted draft status — 16 of whom already have fulfilled their degree requirements and 99 who have not. (According to NFL rules, players can apply for the draft three years after their high-school class graduated).

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Heisman Trophy-winning senior quarterback Joe Burrow (LSU) is widely expected to be selected first overall by the Cincinnati Bengals on Thursday, but in his most recent mock draft released last week, ESPN draft guru Mel Kiper Jr. projects 27 of the 32 picks in the first round will be underclassmen.

Featured on Kiper’s latest list are two Ohio State junior defenders, edge-rusher Chase Young and cornerback Jeff Okudah, going with the next two picks after Burrow, Clemson junior linebacker Isaiah Simmons coming off the board next to the Giants and Alabama tackle Jedrick Wills Jr. landing with the Jets at No. 11. Kiper predicts that fellow Crimson Tide stars such as quarterback Tua Tagovailoa, safety Xavier McKinney and wide receivers Jerry Jeudy and Henry Ruggs III also will be selected in the opening round.

Still, Alabama coach Nick Saban, whose program has had 21 players leave early over the past four years, consistently has railed against the system that forces players to decide in January — months before the NFL Scouting Combine — if they want to leave school without the option of returning.

“It’s the culture and it’s the trend, and I’ve actually changed how I talk to recruits now,” Saban said in 2019. “I tell every recruit that I talk to, the reason that you’re going to college is to prepare yourself for the day you can’t play football.

NFL Draft
2019 NFL DraftGetty Images

“I think we have a lot of people way back in high school, that look at college as a conduit to get to the NFL. … We’ve had six or seven guys here that had second- or third-round grades that became top-15 and first-round draft picks and made a significant amount of money doing that, so there’s some really good examples of guys that did it that way. But I think, [and it’s] not just our players, there’s a significant amount of players that are not making good business decisions about what they do.”

Many undrafted players, of course, still will sign as free agents and occasionally end up on a team’s practice squad, but these deals offer few monetary guarantees. As recently as 2011, the number of players with remaining eligibility to declare for the draft was 56, but that number has nearly tripled over the past nine years.

While the NBA has had success with its G-League to stash prospects in need of further seasoning, the other issue on the NFL side has been the failure for a viable spring developmental league to take hold. The fledgling Alliance of American Football folded after just eight weeks of operation in 2019, while Vince McMahon’s rebooted XFL already has filed for bankruptcy after the league was shut down last month due to the coronavirus pandemic.

Schwartz had suggested a plan last year in a column for SB Nation for the NFL to expand practice squads (from the current 10 players per team) to 22 — with extra coaches, too — and combine with those from other teams to play games a few times per season in a “developmental league [the NFL] has authority over.”

“The NFL would have to back it. But college football is a natural minor league feeder system for the NFL to use. So there’s not a need to pay for it if the league isn’t going to make money off it,” Schwartz said. “I think the NBA is a little different with a smaller roster size and not having to practice as much.

“In the NFL, there’s a far greater opportunity to improve every day in practice. And I just think a lot of players are still willing to take that chance.”