There isn't one defined way to swing a bat — just look at the left-handed swings of Robinson Cano, Ken Griffey Jr., George Brett and Ted Williams. Each had a unique stance that led to beautiful, effective swings.

"We were all very different," Griffey said in 2014. "But all good hitters end up in the same position when the pitch comes. We did that."

The key component of a swing has nothing to do with the bat.

"The legs are the key," Martinez said. "You hear the old saying, 'When the legs go, you are done.' … That's where you get your strength and bat speed. If you use your legs correctly, you can drive the ball to all fields."

And what else is needed?

"A timing mechanism and a swing that comes through the zone is also very important," Martinez said.

Once the swing is initiated, good hitters keep the bat head in the strike zone. They don't flail or reach.

"It starts mentally," then-M's hitting coach Howard Johnson said in 2014. "You have to have conviction and commitment to what you are doing. Without that, nothing is going to happen. That's what I look for. That's where the term 'in-between' comes from. You just aren't sure, you aren't picking up the ball, you aren't ready to hit. So having that conviction and being ready to hit and do those things is priority No. 1."

— Ryan Divish