They used to be considered safe picks, easy-to-identify future stars, the closest thing to guarantees in the NFL's annual crapshoot player-selection process known as the draft. 

But the reputation of offensive tackle prospects has been recently damaged after a string of high-caliber, early-round prospects flopped or have proven to be adequate at best with their respective pro teams.

From 2012 to 2016 there were 14 players drafted in the first round to play offensive tackle. Four are no longer with the club that drafted them. Two have already been moved to guard. One is a clear-cut backup. One is currently an unsigned free agent. Another is on the verge of being cut... today. (The jury is still out on the 2017 and 2018 offensive tackle classes, so they're not included here).

Only Lane Johnson (No. 85) was named to Pro Football Focus' top 101 players after the 2017 season, and he represents one of two All-Pro distinctions from that group. The other went to Jack Conklin, who received the award after his rookie season in 2016.

On the flip side, of the 23 edge-rushers to be picked in the first round from 2012 to 2016, five were on PFF's top 101 list, and four have been named to an All-Pro team. 

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The Ringer's Robert Mays dove deep into the NFL's offensive line epidemic in November of last year and cited former pro linemen turned trainers or media members. His research pinpointed the drastic difference in blocking responsibilities between the college and pro games and identified the prevalence of the spread offense in college, with its quick-passing philosophy, as a main culprit for the widespread issues. Tackles simply didn't have to block for very long on each play before entering the NFL. 

As we've seen with countless other once collegiate-only offensive trends, most namely the shotgun, the bubble screen, the Wildcat, the pistol, the read-option, the spread and run-pass option are now basically ubiquitous. Heck, two quarterbacks, Jared Goff and Patrick Mahomes, who played in the wide-open pass-predominant "Air Raid" system, previously deemed to be a guaranteed indicator a passer wouldn't succeed at the NFL level, are leading the only 5-0 teams in football and have the No. 2 and No. 5 quarterback ratings in the league heading into Week 6. 

According to NFL Next Gen Stats, in 2016, the NFL's Average Intended Air Yards (IAY) among all qualifying quarterbacks was 8.86 yards downfield. Last year, the collective average was 8.33 yards. Through Week 5 in 2018, the league IAY among qualifiers is just 8.05 yards. 

So, despite a contingent of young quarterbacks with the arms to "save" the deep ball, it's obvious the NFL too is becoming -- has become? -- just like college, a quick-passing league that doesn't ask its tackles to block for very long. The NFL's seismic morph into the pro version of the Big 12 is upon us. 

And that's excellent news for offensive tackles. Their jobs have and will continue to get ... easier. 

Also, teams looking for a franchise left or right tackle in the 2019 Draft are in luck, because that position is as loaded at the top as its been in a long time. 

Alabama's Jonah Williams (currently my No. 2 overall prospect) has started on the edge for the Crimson Tide since his freshman season. He's the opposite of a project, a fundamentally sound technician with plus athleticism and developed strength to deal with every type of pass-rusher. While Nick Saban's club is known for its running prowess, its offense utilizes a plethora of spread concepts. 

Ole Miss' Greg Little, another SEC product who's played since his days as a freshman, can get a little sloppy with his technique but is a dancing bear at 6-foot-5 and 325 pounds with heavy hands. He's been the anchor of an offensive line tasked with plenty of pass-blocking.

Out in Manhattan, Kansas, Dalton Risner has been a mainstay at right tackle for going on three seasons now after starting at center to begin his career for the Kansas State Wildcats. He has light feet and is country strong, a combination that helps him dominate even the quickest and most speed-to-power outside-rushers. Just ask Montez Sweat.

Oklahoma's Bobby Evans understands the intricacies of the spread offense playing under Lincoln Riley. At 6-5 and a shade over 300 pounds with deceptive strength, he has the frame to thrive in pass-protection at the NFL level and has considerable experience getting out on a variety of screen plays. 

West Virginia's Yodny Cajuste blocks the blindside in an Air Raid system and is the closest to being "NFL strong" out of all offensive tackle prospects in the country. David Edwards has played since 2016 and is one of the most athletic offensive tackles Wisconsin's had in recent years. He's more than capable in pass-protection, and we know he has ample point-of-attack strength. 

This looks like the best offensive tackle draft class since 2010, that, at the top, featured Trent Williams, Russell Okung, Anthony Davis, and Bryan Bulaga

And NFL teams are finally very close to tailoring their offenses around what their quarterbacks and their offensive tackles know.