Pro Set trading cards product, which could make and issue cards very quickly. For its first football card set in 1989, Pro Set released its cards in three series. The 1989 rookies were found primarily in the second series. Key rookies in the set included Troy Aikman, Barry Sanders, Derrick Thomas, Jeff Lageman and Deion Sanders. The 100 card Series II set was sold in packs, but the packs averaged 11 Series I cards and 4 Series II cards per pack. These cards not only featured first round picks but featured later round picks. These cards were labelled as Pro Set Prospects. At its
Rookie card level of competition within his or her sport.. Collectors may value these first appearances more than subsequent card issues. A rookie card is not necessarily always produced during a player's rookie season because there could have been cards that fit the definition printed in previous years. It is generally agreed that to be a true rookie card, the card must be numbered as part of a product's base set. Thus, insert cards of any type are generally not considered to be rookie cards. In 2006 Major League Baseball instituted a set of guidelines which dictated what cards could and could