MITB Sports -Adult Flex Tennis: Registration Welcome to the MITB Sports Ready to Play Flex League section. MITB Sports - Tennis is making every attempt to show members that we are serious and determined to make your experience a fun and competitive one. This also means that MITB Sports - Tennis is taking SANDBAGGING Very Seriously and we will be moving players levels of play prior to the start of the season. We will be using past seasons of MITB Sports League play, USTA NTRP rating as well as ALTA (Atlanta Lawn Tennis Association) levels. If you are in this area, you are serious about playing and are ready to move forward. Confirm you have read the above information.