Usage / Role
56%
Regular defensive contributor
lowfeatured
Player Dossier
2018-2021Iowa
Jack Koerner
DB • 6'0" • 204 lbs • Des Moines, IA, USA
Ball-hunting defenderSplash play profile
Jack Koerner shows a ball-hunting defender profile with 34.7 disruption score.
Impact Production
85
Top-tier box-score impact for a defensive back
lowelite
Reliability
100
Regular contributor with several takeover games
lowhigh
Star Power
63
Useful peak profile
limitedstar
Career Arc
Value trend by season
Best season by Season Value: 2020 Regular Season · Iowa
181919202121
Snapshot
- Career Teams
- 1
- Unique Seasons
- 4
- Program Path
- Iowa
- Peak Game
- Peak game by takeover score: Purdue
Player Story
Jack Koerner built his college career from 2018 through 2021 as a defensive back from Des Moines, IA wearing No. 28, spending time with Iowa. The clearest part of Jack Koerner's career was his defensive production:...
Read the storyJack Koerner, DB. Best season Best season by Season Value: 2020 Regular Season · Iowa. Jack Koerner shows a ball-hunting defender profile with 34.7 disruption score.
Stat Footprint
Career production snapshot
- Tackles
- 215
- TFL
- 6.5
- QB hurries
- 1
- Passes defended
- 10
Quick Answers
Jack Koerner quick answers
- Latest team and position
- Iowa · DB
- Career Tackles
- 215
- Tracked sample
- 4 unique seasons · 6 entries · 34 games
- Best season
- 2020 Regular Season · Iowa
- Top game
- Purdue
- Latest roster
- No. 28 · Senior
- 2021 Tackles rank
- 88 tackles · DB 11th (top 2%) · Big Ten 15th (top 3%) · National 119th (top 2%)
Season Ledger
Crawlable season-by-season stats
| Season | Team | Games | Tackles | TFL | Sacks | QB Hur | PD | TD | Overall |
|---|---|---|---|---|---|---|---|---|---|
| 2018 Regular Season | Iowa | 1 | 1 | - | 0 | - | - | 0 | 37.8 |
| 2019 Postseason | Iowa | 12 | 8 | 1 | 0 | - | - | 0 | 52.3 |
| 2019 Regular Season | Iowa | 12 | 73 | - | 0 | - | 5 | 0 | 52.3 |
| 2020 Regular Season | Iowa | 8 | 45 | 2 | 0 | 1 | 2 | 0 | 63.6 |
| 2021 Postseason | Iowa | 13 | 5 | 0.5 | 0 | - | 1 | 0 | 54.8 |
| 2021 Regular Season | Iowa | 13 | 83 | 3 | 0 | - | 2 | 0 | 54.8 |
Related Context
Keep exploring Jack Koerner
Jack Koerner played DB for Iowa. Across 4 tracked seasons, Jack Koerner recorded 215 tackles. His top tracked season came in 2021 with Iowa.
Player insights
Lead takeaway
Best season by value score: 2020 Regular Season
Iowa paired 8 primary output with 32.9 efficiency.
Supporting note
2021 Postseason role shape
impact-led usage with 34.7 efficiency.
Supporting note
Career value stayed steady
2021 Regular Season tracked close to the prior stop by season value score.
Supporting note
Peak game by takeover score: Purdue
Loss with 2 impact plays across the defensive snap sheet. It landed in the 100th percentile of the selected season.
Analysis workspace
Season Workbench
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Season Explorer
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2021 Postseason · Iowa
Games
13
Havoc Plays / G
0.7
Efficiency
34.7
Usage
8.3
Consistency
15.4
Best Game by takeover score
Purdue
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Active game
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Game-by-Game Trend
Follow how the selected stat changes from one game to the next. Spikes mark standout outings, while dips show quieter weeks.
Chronological game order.
Game by game trend chart. Kentucky: 1.5. Indiana: 2. Iowa State: 0. Kent State: 1. Colorado State: 0. Maryland: 1. Penn State: 1. Purdue: 2. Wisconsin: 0. Northwestern: 0. Minnesota: 0. Nebraska: 0. Michigan: 0
Volume vs Efficiency
Each dot is a game. Farther right means the player carried more of the workload, and higher means they were more efficient with those chances.
Low volumeHigh quality
High volumeHigh quality
Low volumeLower quality
High volumeLower quality
Volume on the x-axis, quality on the y-axis.
Volume versus efficiency scatter chart. Kentucky: 5 by 35.8. Indiana: 5 by 40.8. Iowa State: 5 by 20.8. Kent State: 7 by 39.2. Colorado State: 6 by 25. Maryland: 2 by 18.3. Penn State: 7 by 39.2. Purdue: 9 by 57.5. Wisconsin: 11 by 45.8. Northwestern: 8 by 33.3. Minnesota: 8 by 33.3. Nebraska: 7 by 29.2. Michigan: 8 by 33.3
Split Comparison
Compare how this player performed across different situations. "Games" shows how many matchups are included in each split.
Wins0.6 · Games = 9 · -0.3 vs Losses
Losses0.9 · Games = 4 · +0.3 vs Wins
Game Log
Dense stat lines with inline explanations and season-linked highlights.
13 games
Featured metric
Havoc Plays
Top game by takeover score
Purdue
Best efficiency game
57.5 vs Purdue
| Result | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sat 1/1 | @ Kentucky | L 17-20 | 5 | 1 | — | 0.50 | 0 | — | 1 | — | — |
| Sun 12/5 | vs Michigan | L 3-42 | 8 | 5 | — | 0 | 0 | — | 0 | — | — |
| Fri 11/26 | @ Nebraska | W 28-21 | 7 | 6 | — | 0 | 0 | — | 0 | — | — |
| Sat 11/13 | vs Minnesota | W 27-22 | 8 | 3 | — | 0 | 0 | — | 0 | — | — |
| Sat 11/6 | @ Northwestern | W 17-12 | 8 | 8 | — | 0 | 0 | — | 0 | — | — |
| Sat 10/30 | @ Wisconsin10+ tackles | L 7-27 | 11 | 9 | — | 0 | 0 | — | 0 | — | — |
| Sat 10/16 | vs PurdueSplash game | L 7-24 | 9 | 5 | — | 2 | 0 | — | 0 | — | — |
| Sat 10/9 | vs Penn State | W 23-20 | 7 | 4 | — | 0 | 0 | 1 | 0 | — | — |
| Sat 10/2 | @ Maryland | W 51-14 | 2 | 2 | — | 0 | 0 | 1 | 0 | — | — |
| Sat 9/25 | vs Colorado State | W 24-14 | 6 | 6 | — | 0 | 0 | — | 0 | — | — |
| Sat 9/18 | vs Kent State | W 30-7 | 7 | 5 | — | 1 | 0 | — | 0 | — | — |
| Sat 9/11 | @ Iowa State | W 27-17 | 5 | 5 | — | 0 | 0 | — | 0 | — | — |
| Sat 9/4 | vs IndianaSplash game | W 34-6 | 5 | 3 | — | 0 | 0 | — | 2 | — | — |
Player Story
Jack Koerner story
Jack Koerner built his college career from 2018 through 2021 as a defensive back from Des Moines, IA wearing No. 28, spending time with Iowa. The clearest part of Jack Koerner's career was his defensive production: 215 tackles, 6.5 tackles for loss, 6 interceptions, and 10 passes defended across 34 career games in the available record. His largest box-score season came in 2021 with Iowa. Those numbers show where he fit, how often the ball or action found him, and how his role developed over time.
Defensive careers can be hard to read from one number, but Jack Koerner's production has multiple signals. With 34 career games in the available record, his career has enough shape to show both opportunity and production across Iowa.
The arc is straightforward: Jack Koerner moved through the depth chart, found a larger role, and turned that opportunity into production that can be understood through standard football numbers.
Career Arc
Track team changes, role shifts, and season-to-season movement.
- 1
Iowa
2018-2021
Opening stop
Season Value Progression
201820192019202020212021
| Season | Team | Primary | Efficiency | Usage | Delta |
|---|---|---|---|---|---|
| 2018 Regular Season | Iowa | 0 | 4.2 | 1.1 | — |
| 2019 Postseason | Iowa | 7 | 33.6 | 5.8 | 7 |
| 2019 Regular Season | Iowa | 7 | 33.6 | 5.8 | 0 |
| 2020 Regular Season | Iowa | 8 | 32.9 | 7.8 | 1 |
| 2021 Postseason | Iowa | 8.5 | 34.7 | 8.3 | 0.5 |
| 2021 Regular Season | Iowa | 8.5 | 34.7 | 8.3 | 0 |
Signature Performances
Top Games
#1 Featured game
vs Purdue
Week 7 · L 7-24 · Conference game
Loss with 2 impact plays across the defensive snap sheet.
2
Havoc Plays
85.8 takeover
2 disruption/tackle impact with 85.8 takeover score.
#2
@ Iowa State
Week 3 · W 18-17
2
Havoc Plays
70.8 takeover
Win with 2 impact plays across the defensive snap sheet.
2 disruption/tackle impact with 70.8 takeover score.
#3
@ Illinois
Week 14 · W 35-21 · Conference game
2
Havoc Plays
70.6 takeover
Win with 2 impact plays across the defensive snap sheet.
2 disruption/tackle impact with 70.6 takeover score.
#4
@ Purdue
Week 8 · L 20-24 · Conference game
1
Havoc Plays
70 takeover
Loss with 1 impact plays across the defensive snap sheet.
1 disruption/tackle impact with 70 takeover score.
#5
@ Nebraska
Week 14 · W 27-24 · Conference game
1
Havoc Plays
63.9 takeover
Win with 1 impact plays across the defensive snap sheet.
1 disruption/tackle impact with 63.9 takeover score.
Top Seasons
#1 Season by Season Value
2020 Regular Season · Iowa
8 primary output · 32.9 efficiency · 7.8 usage
63.6
#2
2021 Postseason · Iowa
54.8
8.5 primary · 34.7 efficiency · 8.3 usage
#3
2021 Regular Season · Iowa
54.8
8.5 primary · 34.7 efficiency · 8.3 usage
Milestones
8
Impact games
5
Splash games
4
10+ tackle games
Next best actions
Keep exploring Jack Koerner
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