Coming in fast, Mack,
following instructions, tore into Dave, hitting him low. Frank's
interference disappeared suddenly and completely in a jolting
somersault and Mack, with a half roll, was upon his feet and diving
back after the man with the ball. Frank tried to elude him and to
forward pass at the last instant but Mack had covered him too fast. He
was tackled before he could get the ball away for a loss of twelve
yards.

"Great stuff!" congratulated a winded Dave who had staggered to his
feet. "That's getting past interference!"

"Now aren't you sorry you wised me up?" smiled Mack, appreciatively.
"You could have had things all your own way."

"But it wouldn't have been any fun," was Dave's reply. "Now I've got
to _work_!"

And Dave's prediction proved correct. A friendly feud developed
between Mack and himself. It was no longer possible for Dave to block
Mack out of the play and keep going himself. Invariably the two went
down and out together. Occasionally Mack would so batter his
interference as to reach the man with the ball himself. If he did not,
he so thoroughly removed the interference that he forced the ball
carrier in the open and made him comparatively easy prey for fellow
Seconds to bring down.

"Dave, you've done wonders for me," Mack said, gratefully, at the end
of a gruelling practice. "I don't know how to thank you."

"Don't try," Dave answered. "I've been watching you for some time. I
knew you were just missing out. You ought to make it tough for anybody
from now on!"

That any fellow player would have been so unselfish as to help a rival
overcome a fault in charging interference and thus jeopardize his own
position on the team was almost beyond Mack's comprehension. Long
after the practice session was over he puzzled Dave's great kindness
and wondered, too, whether Coach Edward had finally been impressed with
the way he had played.

"After I got the hang of it, I made even Dave look bad," Mack told
himself. "I certainly didn't intend to do this ... but every time I
broke up the interference and nabbed Frank it counted in my favor and
against Dave. Coach doesn't know, of course, who's responsible for my
improvement. I only wish it was earlier in the season. I might be
able to get somewhere." But this thought brought a feeling of remorse
since Mack's advancement would ordinarily have to be at Dave's expense.

"I see now what Coach meant about a fellow's playing wholeh