The play-in games will involve the four teams that earn the lowest-ranked automatic qualifiers to the tournament.
The reason for this is that the NCAA wants to maintain a 50-50 balance in the tournament between automatic qualifier and at-large bids. The 2014 tournament will feature 10 automatic qualifiers for the first time, with the additions of berths for the Atlantic Coast Conference and the Atlantic Sun. The play-in games will eliminate two AQ teams from the bracket, leaving eight AQs and eight at-larges.
In 2015, the tournament again will have 10 AQs, with the addition of the Big Ten and the expected dissolution of the Eastern College Athletic Conference's bid.
The tournament expansion follows the NCAA's announcement last week that play-in games in all sports will now be part of tournament brackets and expenses will be covered by the NCAA instead of the teams.
Jim Siedliski, NCAA men's lacrosse championships committee chairman, told Lacrosse Magzine that the earliest the tournament could grow to 20 teams is spring 2016.
Next spring, M&T; Bank Stadium will host Championship Weekend for the first time since 2011.