We were kicking around Trey Lance’s potential yesterday. I have concerns about when he’ll be ready. He’s a young guy, and he started only one game last year (completing 15 of 30 for 149 yards against Scottie Pippen’s old school).

Lance was only 20 when the 49ers drafted him. He’s 21 now.

I ran some numbers on this. They’ve got some cool search tools at Pro-Football-Reference. In the last 20 years, there have been 105 games started by quarterbacks who are 21. The track record isn’t good.

Those quarterbacks went 31-74 in those starts, with 106 touchdowns and 130 interceptions. As a group, they completed 55.7 percent of their passes in those games, averaging 203 passing yards. And 273 sacks (about 2.6 per game).

Only 24 of those 105 quarterbacks threw multiple touchdowns. (I’ve got those guys tagged with black dots.)

The games listed are all of the regular-season variety. (One playoff game by a 21-year-old in the last 20 years, with Lamar Jackson losing against the Chargers.)

With the 49ers, I’m thinking they’ll go to camp with their two quarterbacks and see what happens. And I would guess that Jimmy Garoppolo, with his experience and command of the offense, will probably be starting on opening day.

The situation played out similarly with the last North Dakota State quarterback. The Eagles were thinking they’d bring Carson Wentz along slowly, with Sam Bradford being their starter. But Wentz exceeded expectations in the preseason and Teddy Bridgewater tore his ACL, giving the Eagles the opportunity to move him for a first-round pick.

As a rookie, Wentz wasn’t as mobile as Lance but had more college experience.

If we’re drafting San Francisco quarterbacks today, I would take Garoppolo if I’m looking for someone who needs to play in September. If it’s more of a lottery-pick choice as a third or fourth quarterback, I would go with Lance. (I don’t think Lance will be as effective as a passer this year, but whatever the difference would be would easily be wiped out by what Lance will do as a runner.)

On the chart below, the youngest guys are listed first.

21-YEAR-OLD STARTING QUARTERBACKS (since 2000)
PlayerYearOppResultCmpAttCmp%YdsTDInt
• Sam Darnold, NYJ2018@DETW 48-17162176.219821
Sam Darnold, NYJ2018MIAL 12-20254161.033412
Sam Darnold, NYJ2018@CLEL 17-21153148.416902
Sam Darnold, NYJ2018@JAXL 12-31173450.016710
• Sam Darnold, NYJ2018DENW 34-16102245.519831
• Sam Darnold, NYJ2018INDW 42-34243080.028021
Sam Darnold, NYJ2018MINL 17-37174240.520613
Michael Vick, ATL2001DALW 20-1341233.33210
Sam Darnold, NYJ2018@CHIL 10-24142948.315310
Sam Darnold, NYJ2018@MIAL 6-13213953.922904
Alex Smith, SFO2005INDL 3-2892339.17404
Alex Smith, SFO2005@WASL 17-5281650.09201
Sam Darnold, NYJ2018@BUFW 27-23162466.717011
• Sam Darnold, NYJ2018HOUL 22-29243863.225320
Michael Vick, ATL2001@STLL 13-31123040.017601
• Sam Darnold, NYJ2018GNBL 38-44243568.634130
Sam Darnold, NYJ2018@NWEL 3-38162857.116700
Alex Smith, SFO2005ARIL 10-17162466.718503
Matthew Stafford, DET2009@NORL 27-45163743.220503
Alex Smith, SFO2005@SEAL 3-4192240.97701
Matthew Stafford, DET2009MINL 13-27183060.015212
Alex Smith, SFO2005@JAXL 9-1082433.312301
Alex Smith, SFO2005@STLW 24-20121675.013100
Matthew Stafford, DET2009WASW 19-14213658.324110
Josh Rosen, ARI2018SEAL 17-20152755.618010
Matthew Stafford, DET2009@CHIL 24-48243666.729611
Josh Rosen, ARI2018@SFOW 28-18102540.017010
Alex Smith, SFO2006HOUW 20-17162955.215911
Josh Rosen, ARI2018@MINL 17-27213167.724001
• Jameis Winston, TAM2015TENL 14-42163348.521022
DeShone Kizer, CLE2017PITL 18-21203066.722211
Josh Rosen, ARI2018DENL 10-45213953.919413
Jameis Winston, TAM2015@NORW 26-19142166.720710
DeShone Kizer, CLE2017@BALL 10-24153148.418203
• Josh Rosen, ARI2018SFOW 18-15234057.525221
• DeShone Kizer, CLE2017@INDL 28-31224746.824223
Jameis Winston, TAM2015@HOUL 9-19173647.226111
Matthew Stafford, DET2009STLL 10-17143342.416801
• Jameis Winston, TAM2015CARL 23-37264360.528724
DeShone Kizer, CLE2017CINL 7-31163447.111801
• Matthew Stafford, DET2009@SEAL 20-32224252.420325
Josh Rosen, ARI2018@KANL 14-26223956.420812
Jameis Winston, TAM2015JAXW 38-31131968.420910
DeShone Kizer, CLE2017NYJL 14-1781747.18701
• Josh Rosen, ARI2018OAKL 21-2392045.013632
Matthew Stafford, DET2009@MINL 10-27295156.922410
• Matthew Stafford, DET2009CLEW 38-37264360.542252
Josh Rosen, ARI2018@LACL 10-45121963.210511
• Jameis Winston, TAM2015@WASL 30-31212972.429720
Matthew Stafford, DET2009GNBL 12-34204346.521314
DeShone Kizer, CLE2017TENL 9-12122060.011402
Josh Rosen, ARI2018@GNBW 20-17112642.314900
• Josh Freeman, TAM2009GNBW 38-28143145.220531
Jameis Winston, TAM2015@ATLW 23-20162955.217710
DeShone Kizer, CLE2017MINL 16-33183452.917900
Josh Rosen, ARI2018DETL 3-17264163.424001
Matthew Stafford, DET2009@CINL 13-23112642.314312
Josh Freeman, TAM2009@MIAL 23-25162857.119611
Jameis Winston, TAM2015NYGL 18-32193652.824700
Josh Rosen, ARI2018@ATLL 14-40132259.113202
DeShone Kizer, CLE2017@DETL 24-38213756.823211
Jameis Winston, TAM2015DALW 10-6223956.426402
Josh Freeman, TAM2009NORL 7-38173351.512613
Lamar Jackson, BAL2018CINW 24-21131968.415001
Josh Rosen, ARI2018LARL 9-31122352.28700
• Marcus Mariota, TEN2015@TAMW 42-14131586.720940
• Jameis Winston, TAM2015@PHIW 45-17192965.524650
• Josh Freeman, TAM2009@ATLL 17-20202969.025020
DeShone Kizer, CLE2017JAXL 7-19163250.017912
Teddy Bridgewater, MIN2014ATLW 41-28193063.331700
Lamar Jackson, BAL2018OAKW 34-17142556.017812
Josh Rosen, ARI2018@SEAL 24-27183452.914910
• Marcus Mariota, TEN2015@CLEL 14-28213756.825720
Jameis Winston, TAM2015@INDL 12-25203655.624511
Josh Freeman, TAM2009@CARL 6-16234452.332105
DeShone Kizer, CLE2017@CINL 16-30183158.126800
Lamar Jackson, BAL2018@ATLW 26-16122157.112500
• Marcus Mariota, TEN2015INDL 33-35274461.436722
Jameis Winston, TAM2015ATLW 23-19182766.722711
DeShone Kizer, CLE2017@LACL 10-19153246.921511
Josh Freeman, TAM2009NYJL 3-26143342.49303
Lamar Jackson, BAL2018@KANL 24-27132454.214720
Teddy Bridgewater, MIN2014DETL 3-17233762.218803
• DeShone Kizer, CLE2017GNBL 21-27202871.421432
• Josh Freeman, TAM2009@SEAW 24-7162661.520521
Jameis Winston, TAM2015NORL 17-24183256.318210
Teddy Bridgewater, MIN2014@BUFL 16-17152657.715712
Lamar Jackson, BAL2018TAMW 20-12142360.913110
• Jameis Winston, TAM2015@STLL 23-31295058.036321
Blaine Gabbert, JAX2011@CARL 10-16122157.113911
Marcus Mariota, TEN2015BUFL 13-14213265.618701
Josh Freeman, TAM2009@NORW 20-17213167.727102
DeShone Kizer, CLE2017BALL 10-27203754.114602
Lamar Jackson, BAL2018@LACW 22-10122254.620410
Teddy Bridgewater, MIN2014@TAMW 19-13244257.124110
Blaine Gabbert, JAX2011NORL 10-23164238.119611
Marcus Mariota, TEN2015MIAL 10-38213363.621912
• Jameis Winston, TAM2015CHIL 21-26152951.729521
Josh Freeman, TAM2010ATLL 10-20153148.417212
DeShone Kizer, CLE2017@CHIL 3-20183650.018202
Teddy Bridgewater, MIN2014WASW 29-26264261.926810
Lamar Jackson, BAL2018CLEW 26-24142458.317900
Blaine Gabbert, JAX2011CINL 20-30152853.622110
• DeShone Kizer, CLE2017@PITL 24-28163053.331421
Jameis Winston, TAM2016@CARL 10-38294761.732502

Statistics compiled using search tools at Pro-Football-Reference.com

—Ian Allan