By Major League Baseball rules, teams are allowed to expand their active rosters on the first of September. Players promoted have to be on the current 40-man roster. Teams usually take the opportunity to add a few bats and arms if they are in contention for playoff spots or take a look at young players if they are already planning for next year. They can make their move on September 1st or wait until the Triple-A season ends on September 7th. The Tampa Bay Rays are on the border here as a team with a slim chance to make the playoffs who also needs to look towards 2016.