On Jan. 1, more than 30 changes to the Rules of Golf -- some small, others significant -- will take effect. To get you ready, this holiday season GOLF.com is rolling out a series, “The 12 Days of Rules Changes,” to ensure you always play by the rules, starting with your opening round of the year. The Topic: Repairing damage (spike marks!) on the putting green The Old Rule: A player may only repair ball-marks or old hole plugs on the putting green. The New Rule: Golfers are now allowed to repair almost any damage on the green, such as spike marks, ball-marks, indentations from a club or flagstick, and animal damage. They are not permitted to repair aeration holes, natural surface imperfections, or natural wear of the hole. USGA believed that players should not be prohibited from repairing other types of damage on the green. Will It Be Controversial?: Allowing the repair of all damage on the putting green could lead to every golfer's worst nightmare: slow play. If players try to repair too many areas, play could slow down. But according to the USGA, slow play rules should mitigate any risk of players making excessive repairs on the green and can guard against it becoming an issue.