There are certain types of ballplayers you need for a team to succeed.  You need talent and hustle, but they come in different forms.  There are the ones who are born with all the physical tools in the world; the ones who make it look easy.  There are those with lesser gifts, but a work ethic that would put oxen to shame.  Then there  are the scrappers; they may not have as much talent, but their enthusiasm is infectious.

There are, of course, combinations of these archetypes.  Ideally, you want someone who embodies all three to their fullest degree.  Jack has already shown his enthusiastic side.  During his last tee ball game, only his third, he regularly encouraged his teammates, yelling from the bench ("Go yellow team!"), and from the field ("Ready positions, everyone.)