He felt that his blows were too powerful, especially that from the right fist when it should curve over Spike's left shoulder to stop on his jaw.

But he learned that when his glove reached the right place Spike's jaw had for some time not been there.

Spike scorned his efforts.
"Stop it, kid! You might as well send me a pitcher postcard that it's comin'.

You got to hit from where you are--you can't stop to draw back.
Use your left more.

G'wan now, mix it! Mix it!" They would mix it until the boy was panting.