In his debut, Brett Phillips caught Denard Span off-guard with his arm

One of the advantages a player has in his Major League debut is that "the book" is not yet out on his strengths and weaknesses. Some of that advantage may have diminished a bit with developments in analytics, scouting, and the flow of information, but it still seems to be the case.
Take for example Brewers outfielder Brett Phillips. Monday night's 7-2 loss to the Giants was Phillips' debut. Despite scouting reports indicating that his arm was one of his strongest tools -- MLB.com puts a 70 grade on it -- that information was lost on Denard Span who tried to stretch this single into a double.

Speaking to MLB.com's Adam McCalvy, Phillips attributed his laser throw to a rush of adrenaline fueled by a teammate. "Luckily, [left fielder] Nick Franklin was yelling, 'Two! Two! Two!'," Phillips said. "Got me fired up."
As the book on Phillips goes through its publication, more players may react to his arm much in the way he reacts to opossums.