Blocking movement in the run game is one of the hardest skills to teach because the defense rarely stays still—late shifts, gap exchanges, and second-level rotation can pull linemen out of their rules. The goal isn’t to chase color; it’s to keep eyes disciplined, communicate the picture, and execute your assignment even when the front changes.
Your linemen are fine when the picture is clean. But once you get gap exchanges, late movement, or second-level rotation, guys tend to “lock in” to the pre-snap label and start playing the wrong game. Mike Hallett put it plainly: his players were so tied to the call and the box count that movement pulled them out of their rules.
The problem usually isn’t effort. It’s eyes and assignment discipline.
Hallett shared a drill at the C.O.O.L. Clinic that trains exactly that, without needing a perfect scout look. He calls it Med Ball Stack.
The core idea: take the “structure” away
Most movement issues show up when players depend on structure:
- “It’s this front.”
- “It’s that box.”
- “It’s that call.”
Then the defense moves… and the blocker panics, chases color, or abandons the inside threat.
Hallett’s solution is simple: don’t spend the rep trying to recreate every defense. Instead, remove structure so the OL has to keep their eyes right and execute responsibilities.
The drill setup: “Med Ball Stack”
Alignment (3 defenders)
- Put three defenders in a stack:
- one aligned over the tackle,
- one over the center,
- one inside (three-man surface picture).
Offense
- You’re simulating zone work to the right, and you’re coaching three tracks:
- inside track
- mid-zone track
- stretch track
Constraint that matters
- “Tight end is out on the overhang player. The box is ours.”
That one sentence stops the drill from turning into a free-for-all. Everyone is accountable to the box.
The communication piece: make the center own it
Hallett coaches it like a three-man surface. The center has to see it, declare it, and communicate it:
- “This needs to be a three-man surface.”
- He makes the call (Hallett calls it “trim”), which is three to the Mike.
Even if your terminology is different, the lesson is universal: the center can’t wait for the perfect look. He has to identify and distribute.
The assignment discipline piece: “ultimate A / ultimate B”
Here’s where the drill really earns its keep.
Hallett teaches the backside players:
“I have ultimate A and ultimate B, and I’m not going to chase color out.”
That’s the exact moment a lot of teams break down. Backside movement makes the tackle or guard feel like they need to “help,” and they vacate the inside threat.
So Hallett builds the rep around one coaching emphasis:
- Watch the backside tackle. Don’t chase the second player out if there’s still an inside threat.
How the drill works: numbered defenders, changing patterns
You (the coach) control the chaos.
- Assign numbers to the defenders: 1, 2, 3 (both play side and backside).
- Then you change the pattern every rep:
- “You’re 2. You’re 3. You’re 1.”
- Backside: “You’re 1. You’re 3. You’re 2.”
The players have to ID, communicate, and execute their rules in real time. That’s the whole point.
Again, Hallett isn’t trying to mimic only odd fronts or only one defense. He’s training the skill: eyes + responsibility under movement.
What you coach on every rep: “inside zone demeanor”
The finish matters. Hallett wants the OL to play the rep with the right attitude and landmarks:
- Block on the angle
- Wash the hash
- Give the back a cutback lane
If your players “win” the assignment but lose the demeanor, you’ll feel it on Friday night.
A simple 10-minute install (you can run tomorrow)
Walkthrough (Minute 0-2)
- Align the three-man stack.
- Explain “box is ours.”
- Center makes the call and echoes the distribution.
Half-speed reps (Minute 3–6: )
- Run inside track only.
- Coach the backside tackle: inside threat first, no chasing.
Full-speed reps (Minute 7–10: )
- Mix all three tracks.
- Change numbers every rep.
- Demand communication before movement.
Keep the reps short. Rotate fast. The value is repetition under changing pictures.
One takeaway to carry into team periods
Movement is going to happen. Gap exchanges are going to show up. Your best answer is not a thicker call sheet.
It’s a weekly training plan that teaches linemen to:
- see the box clearly,
- communicate distribution, and
- stay disciplined with ultimate threats instead of chasing color.
That’s what Med Ball Stack is really doing.
About Mike Hallett
Mike Hallett is a veteran college football coach who most recently served as the co-offensive coordinator and offensive line coach at the University of Toledo. He previously led programs as head coach at Heidelberg (2007–2015) and Thomas More (2004–2006). A former Mount Union standout, Hallett is a two-time All-American and was named Division III Lineman of the Year (1993); he later earned OAC Coach of the Year (2011) honors.
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