Duane Burleson/Associated Press

The San Francisco 49ers’ offense last season was so slow, it belonged in the Big 10.

It might have been the slowest offense in the NFL. We’re talking no speed. Well, that’s not entirely true. Colin Kaepernick was fast. Unfortunately, he couldn’t throw the ball to himself.

Kaepernick was the fastest player on the Niners' offense in 2014. For years, tight end Vernon Davis was their fastest player. Last season, he looked slow. At the 2006 combine he ran a 4.38 40-yard dash, but last season he looked like a 4.6-guy at best. He finished the season with just 245 receiving yards—a career low.

The Niners' top three receivers last season were Michael Crabtree, Stevie Johnson and Anquan Boldin. Boldin is slower than Vernon Davis and Niners backup tight end Vance McDonald. Boldin runs a 40-yard dash in 4.72 seconds—practically slow motion.

Crabtree never was fast to begin with, but in 2014 he seemed slower than Boldin. Crabtree averaged just 10.3 yards per catch. He never bounced back from tearing his Achilles in 2013.

Of the Niners' top three receivers, Stevie Johnson was the fastest. And he averaged 12.4 yards per catch. Quite the deep threat.

The Niners didn’t have a deep threat. They didn’t have a fast running back, either. Kendall Hunter tore his ACL during training camp, and the two remaining running backs were Frank Gore and Carlos Hyde.

The opposing defense could pack itself between the tackles because it knew both Gore and Hyde would run up the middle. Neither running back was fast enough to bounce runs outside and turn the corner against NFL defenses. The Niners' running game was limited and predictable.

The entire offense was limited and predictable. Most plays were short passes or inside runs. The other team could bog down the Niners' offense simply by standing close to the line of scrimmage. Suddenly, holes in the Niners' running game disappeared and passing windows shrank to the size of peep holes.

An offense can’t function with that much congestion. An offense can’t consistently bulldoze its way down the middle of the field in the NFL. A good NFL offense forces the opposing defense to defend the entire field. A good NFL offense needs speed—it can’t be merely tough.

49ers' general manager Trent Baalke understands tough. He built the Niners to be the toughest team in the league. But if toughness is all the Niners have, what happens when they face a tougher team? The Niners lose, that’s what happens.

To Baalke’s credit, he seems to have recognized a gap in his team-building template. He let three of the Niners slowest free agents sign with other teams this offseason. Goodbye, Gore. Goodbye, Crabtree. Goodbye, Johnson.

Baalke replaced them with three fast players—former Baltimore Ravens wide receiver Torrey Smith, former Minnesota Vikings wide receiver Jerome Simpson and former Detroit Lions running back Reggie Bush.

Now, Bush is the Niners fastest player on offense—he ran a 4.37 40-yard dash at his pro day in 2006. He gives the Niners an outside running threat, and he stretches the opposing defense from sideline to sideline when he’s in the game.

Bush also gives Kaepernick an explosive check-down receiver. The past few years, Kaepernick mostly checked down to himself, meaning he kept the ball and scrambled. He rarely threw a pass to a running back.

Instead of trying to be a hero, Kaepernick can dump the ball off to Bush. Let him do the work. Bush is quicker and faster than Kaepernick, anyway.

Torrey Smith is faster than Kaepernick, too. Smith is the Niners’ second fastest player on offense. He’s a straight-line sprinter who forces safeties to back up and play far away from the line of scrimmage. If they don't, Smith will run past them.

Once they back up, everyone on offense gets more room to work. Hyde gets room to run between the tackles, Kaepernick gets room to run the read option, and Boldin, Davis and Bush get space to catch passes over the middle.

Smith is the offense’s decongestant.

Simpson is another decongestant. He’s the No. 3 receiver, and he's a deep threat, like Smith. When the Niners use three receivers, Smith and Simpson can line up on opposite sides of the formation. The threat of their deep speed will force the other team to defend the entire field.

Finally, the 49ers have an NFL offense.

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