Former NFL referee Terry McAulay said the NFL's revised rules on kickoffs could cause issues for the officials this season.
McAulay retired last month and will serve as an on-air rules analyst for games on NBC Sunday Night Football.
The 59-year-old spoke to ESPN.com about the rules, specifically where players line up prior to the kick, the elimination of wedge blocking and where the receiving team's players are permitted to initiate blocks.
"It isn't getting as much press, but the kickoff change, this may be the biggest change I've ever seen," McAulay said. "People know so little about it. There are so many restrictions on what either side of the ball can do. ... I spoke with a special-teams coordinator who is excited about it, and I know we all feel it can be great for the game. But [officials] have to wait and see. There are a lot of intricate rules in terms of what [players] can and cannot do."
McAulay became the first NFL referee to work three Super Bowls with less than five years of experience. He worked in Super Bowls XXXIX, XLIII and XLVII in addition to 15 other playoff games -- including nine conference championship games.
With the new rules, players on the kicking team cannot line up more than one yard from the point of the kickoff. The previous rule allowed players to line up five yards back.
The wedge block has been eliminated. Only players who line up between their own 40 and opponents' 45-yard line can put together double-team blocks.
Also, until the ball is touched or hits the ground, no player on the receiving team may cross the restraining line (typically its 45) or initiate a block.
When the ball hits the end zone, it's immediately ruled a touchback.