What is defacto boston celtics?

As an AI language model, I do not have access to current news or events. However, I can provide general information about the Boston Celtics.

The Boston Celtics are a professional basketball team based in Boston, Massachusetts. They were founded in 1946, and have won a total of 17 NBA championships, which is the most in NBA history for any single franchise, along with the Los Angeles Lakers.

The Celtics have a strong rivalry with the Lakers, as the two teams have faced each other numerous times in NBA finals, making it one of the most historic and intense rivalries in sports.

The Celtics have had several legendary players throughout their history, including Bill Russell, Larry Bird, and Paul Pierce. They play their home games at TD Garden and their current head coach is Brad Stevens.