AJ McCarron broke his collarbone last night, and that's probably a season-ender. Put it this way, the Bills won't be holding a spot on the 53-man roster for AJ McCarron. The odds of Josh Allen starting right away have naturally increased; it will be either him or Nathan Peterman.

The smart money says it will be Allen; that's how things generally go with quarterback selected in the top 10 (the first round, really). Patrick Mahomes sitting all last year is the exception. Peterman has actually been fairly impressive this preseason himself, but if he's the starter in Week 1, he'll just be keeping the seat warm.

Allen, however, has completed just 56.3 percent of his passes (18 of 32) in the preseason, an ironic figure since that's exactly the percentage of his passes that he completed at Wyoming last season. That's better than only three of the quarterbacks drafted in the first round this century. Two of the ones who were worse quickly flamed out of the NFL, Jake Locker and Kyle Boller. The third, Michael Vick, had an up-and-down career; fair to say it was his difference-making ability as a runner that drove much of his NFL success.

COMPLETION PERCENTAGE, FINAL YEAR OF COLLEGE, 1ST-RD QBS (2000-)
YearPkPlayerComAttPctYdsTDInt
201222Brandon Weeden, Clev.40856472.347273713
20044Philip Rivers, NYG34848372.04491347
20122Robert Griffin III, Wash.29140671.74293376
20121Andrew Luck, Ind.28840471.335173710
201432Teddy Bridgewater, Minn.30342771.03970314
20181Baker Mayfield, Clev.28540470.54627436
201422Johnny Manziel, Clev.30042969.941143713
200525Jason Campbell, Wash.18827069.62700207
200411Ben Roethlisberger, Pitt.34249569.144863710
20152Marcus Mariota, Tenn.30444568.34454424
20172Mitchell Trubisky, Chi.30444768.03748306
201316EJ Manuel, Buff.26338768.033972310
20071JaMarcus Russell, Oak.23234267.83129288
201025Tim Tebow, Den.21331467.82895215
20143Blake Bortles, Jac.25938267.83581259
20051Alex Smith, S.F.21431767.52952324
200018Chad Pennington, NYJ29243367.440063812
20037Byron Leftwich, Jac.33149167.442683010
201712Deshaun Watson, Hou.38857967.045934117
201626Paxton Lynch, Den.29644366.83776284
200524Aaron Rodgers, G.B.20931666.12566248
20111Cam Newton, Car.18528066.12854307
20095Mark Sanchez, NYJ24136665.832073410
200610Matt Leinart, Ariz.28343165.73815288
201710Patrick Mahomes, K.C.38859165.750524110
20151Jameis Winston, T.B.30546765.339072518
20063Vince Young, Tenn.21232565.230362610
20021David Carr, Hou.30847664.74299427
20161Jared Goff, LAR34152964.547194313
200818Joe Flacco, Balt.33152163.54263235
201110Blaine Gabbert, Jac.30147563.43186169
20031Carson Palmer, Cin.30948963.239423310
20183Sam Darnold, NYJ30348063.141432613
201810Josh Rosen, Ariz.28345262.637562610
20162Carson Wentz, Phil.13020862.51651174
20041Eli Manning, S.D.27544162.436002910
200722Brady Quinn, Clev.28946761.93426377
20128Ryan Tannehill, Mia.32753161.637442915
201112Christian Ponder, Minn.18429961.52044208
20091Matthew Stafford, Det.23538361.434592510
200422J.P. Losman, Buff.25142259.530773314
20083Matt Ryan, Atl.38865459.345073119
200611Jay Cutler, Den.27346259.13073219
201832Lamar Jackson, Balt.25443059.136602710
200917Josh Freeman, T.B.22438258.62945208
20023Joey Harrington, Det.18632257.82415235
200322Rex Grossman, Chi.28750357.134022217
200232Patrick Ramsey, Wash.25644957.029352213
20101Sam Bradford, St.L.396956.556220
20187Josh Allen, Buff.15227056.31812166
20118Jake Locker, Tenn.18433255.42265179
20011Michael Vick, Atl.8716154.0123486
200319Kyle Boller, Balt.22542153.428152810

In the table, this year's first-round quarterbacks are in bold. On Allen's behalf, some other sub-60 percent passers have gone on to be pretty successful: Matt Ryan, Jay Cutler and Sam Bradford (injuries aside). And some of the guys near the top quickly flopped (Brandon Weeden, Johnny Manziel).

Watching Allen play, I think he's going to be better than I anticipated back when he was drafted. There will be some bumps and hiccups along the way, and there's no getting around he's working behind a questionable offensive line with suspect receiving talent. And if LeSean McCoy is suspended, the quarterback could really find himself helming a sinking ship.

But Allen himself looks OK. If his confidence isn't shattered while the team adds talent around him, he could be pretty good. This 2018 quarterback class by and large looks like it's going to be one we're watching for many years to come.

--Andy Richardson