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Table: Andrew Witherspoon/Axios

Kyle Shanahan uses the same zone-running scheme that his father, Mike, used to lead the Broncos to back-to-back Super Bowls in the late 1990s.

Zone blocking, explained: Offensive linemen block a space instead of a person. This requires mobility (hence why San Francisco has the NFL's lightest O-line) and running backs who can get through holes quickly, rather than dance in the backfield à la Le'Veon Bell.

  • "For a lot of players, that approach requires unlearning years of what they've been taught," writes The Ringer's Danny Heifetz. "If less-heralded running backs pick up the system, they can earn the job — even if they've previously been cut six times." (See: Raheem Mostert.)

What they're saying: Future Hall of Fame LT Joe Thomas said Shanahan's scheme was his favorite offense he ever played in.

"It was like a computer program where everything was dichotomous; it was either a zero or a one and you knew exactly what you had to do on every single play and why."

On defense... The Chiefs have one of the worst run defenses in the NFL. Their best bet at disrupting San Francisco's attack is 311 pound DT Chris Jones, who will try to wreak havoc on the interior against an O-line built for speed not brawn.

The bottom line: The marquee matchup — Mahomes vs. the 49ers — may not end up being the decisive one, as the action on the other side of the ball reflects a bigger point of differentiation between the two teams.

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Updated 7 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Annelise Capossela/Axios

  1. Global: Total confirmed cases as of 6:30 p.m. ET: 20,177,521 — Total deaths: 738,716 — Total recoveries: 12,400,156Map.
  2. U.S.: Total confirmed cases as of 6:30 p.m. ET: 5,130,784 — Total deaths: 164,603 — Total recoveries: 1,670,755 — Total tests: 62,513,174Map.
  3. States: Georgia reports 137 coronavirus deaths, setting new daily record Florida reports another daily record for deaths.
  4. Health care: Trump administration buys 100 million doses of Moderna's coronavirus vaccine.
  5. Business: Moderna reveals it may not hold patent rights for vaccine.
  6. Sports: Big Ten scraps fall football season.

Voters cast ballots in Minnesota, Georgia, Connecticut, Wisconsin and Vermont

Photo: Spencer Platt/Getty Images

Primary elections are being held on Tuesday in Minnesota, Georgia, Connecticut, Vermont and Wisconsin.

The big picture: Georgia and Wisconsin both struggled to hold primaries during the coronavirus pandemic, but are doing so again — testing their voting systems ahead of the general election. Rep. Ilhan Omar (D-Minn.) is facing a strong challenger as she fights for her political career. In Georgia, a Republican primary runoff pits a QAnon supporter against a hardline conservative.

36 mins ago - Health

Trump administration buys 100 million doses of Moderna's vaccine

A volunteer in Moderna's vaccine clinical trial receives a shot. Photo: Paul Hennessy/NurPhoto via Getty Images

The U.S. government has agreed to buy 100 million doses of Moderna's experimental coronavirus vaccine for $1.5 billion, or $15 per dose.

Why it matters: The Trump administration, through Operation Warp Speed, has now bought initial batches of vaccines from Moderna, GlaxoSmithKline and Sanofi, Pfizer, Novavax, Johnson & Johnson and AstraZeneca before knowing whether they are safe and effective. The federal government also appears to own some of the patent rights associated with Moderna's vaccine.